I'm so glad this game got an update so I figured I'd write a guide. The people over at sad panda are absolutely amazing and knocked it out of the park for best girl. Sincerely Neko (the guide author)

This is a guide on the Peanut DLC that has info on the choices for her events and dates.
For dates the optimal choices are in bold.

All of Peanut's events aside from those that overwrite base events (her small cameo) are Purple and not Yellow meaning you can do her story and a major event in the same time slot keeping the consistency of other guides

This guide was written with the 18+ DLC enabled so some choices may differ
You will need to start a new run to activate the DLC

For a guide on the game in general check out this one written by Falcon
https://test-steamproxy.haloskins.io/sharedfiles/filedetails/?id=2855586058

In case you missed an achievement and don't want to dig through the guide here is how to obtain every single one
Double Valentines: Say "It would literally be a dream..." on July 9th
Kick the Can: Pick the Kick the trashcan option on July 10th
Special delivery: Pick "Stay quiet" on July 11th (Might also be automatic if you finish this event)
Hedging your bets: Help peanut trim the bushes on July 15th
Flirting with danger: Flirt with Fumi during the July 16th morning event (requires Suave lvl 1)
Party Animal: Finish the July 16th Evening event
Kiss the girl: Kiss Peanut during date 2
I choose you: See Peanut's ending (Achieve the good ending with all of Peanut's dates finished)

Although complex questions like "Why is Peanut, What is Peanut, Who is Peanut?" are hard to answer the simple reason you should do the Peanut route is that she's cute and nice.

What is Peanut?
Peanut is a character who appears in both Hush Hush and Crush Crush

Who is Peanut?
Peanut Valentine is the younger cousin of Bonnibel Valentine and she even appears in the base game as a cameo in one of Bonnibel's mall events. In both Hush Hush and Crush Crush she's a sweet and caring college student in a stem field which we love to see.

Why is Peanut?
Although hush hush diverges from the continuity of crush crush Peanut is the best version of herself and she finally has room to shine.

The player runs into Peanut on July 6th where she breaks the players watch putting a spin on the typical crush crush formula. Peanut vows to make it up to the player before they leave at the end of the month, by hanging out with them. As the player progresses through the game they'll run into Peanut doing a few jobs here and there to pay for her college tuition. Will the protagonist get to see Peanuts soft and caring nerdy side while they become friends or even more? Find out by playing the Peanut DLC.

The first day you can access the new content is July 5th in the morning. She will appear at the beach with her face as the icon, due to not being an event this won't consume a time slot.

Choice 1:
Paradox: continues the event
What's up: continues the event
Be alone right now: Ends the event

Choice 2:
You were watching me?: Continues the event
Are you okay?: Continues the event
My heart cant take it (suave lvl 1): Affection boost

Choice 3:
All three options have the same result

Choice 4:
You seem to be in distress: Event continues
Pat her head: Affection up
Sneak away: Event ends

Choice 5:
All three options have the same result

Choice 6:
What did you just call me: No affection
Well I wasn't going to buy...: Affection up
Your excitement is literally the best: Affection up (gives more)

Choice 7:
All three options have the same result

Choice 8:
Sure, Peanut: continues the event
Make sure to fill'er up: continues the event
This watch is a heirloom: Ends the event

Choice 9:
All three options have the same result

Choice 10:
All three options have the same result

Choice 11:
If it means that much to you: Affection up
we'll trade numbers: No affection
I don't think so: Ends the event

Choice 12:
Probably for the best: No affection
Don't mention it: Affection up
It's just things: Affection up (Gives more)

July 7th evening
Peanut has an event at the beach
Choice 1:
Talk to her: continues event
Leave her be: ends event
Seagull: Continues event

Choice 2:
I'm just what you need?: Affection up
Fancy running into you again: neutral
I can probably help with several of those problems: Neutral

Choice 3:
I like hearing you talk about the tides: Affection up (slightly more)
You don't strike me as someone...: neutral
Try not to let it get you down: Affection up

Choice 4:
It'll make a difference: Affection up
Hit me with your best shot: Neutral
I got a lot going on: Neutral

July 8th morning
Peanut will have an event at the bakery
Choice 1:
Where's Bonnibel?: Affection up
Icing in your hair: Neutral
You don't look like a starving college student: affection up

Choice 2:
All three options have the same effect

Choice 3:
All choices in this string are neutral "happy for the nice weather" after you pick an option progresses the conversation

Choice 4:
All three options have the same effect

Choice 5:
Bad idea: neutral
Look at these arms (buff lvl 1): Affection up (gives more)
What's the worst that can happen: Affection up

Choice 6:
High five: Affection up (gives more)
Leave her hanging: Neutral
Fist bump: affection up

Choice 7:
Both options are neutral

Choice 8:
All three options have the same effect

Choice 9:
Check the water tank: Neutral
That's bad news (tech savvy lvl 1): Neutral but boost tech savvy skill
Better hit the dusty trail: neutral

Choice 10:
All three options have the same effect

Choice 11:
All three options have the same effect

July 9th morning
Peanut has an event at the bakery

Choice 1:
...And the cookies: Affection up
You're still allowed in the bakery: Neutral
... TWO beautiful women in aprons: Affection up (gives more)

Choice 2:
Doing good: neutral
I know what you mean: affection up
My day just got a LOT better (suave 1): affection up

Choice 3:
A lot on my plate: neutral, ends event
I was promised cookies: Neutral, ends event
It would literally be a dream: Continues event (achievement double valentines)

Choice 4:
Thanks bonbon: neutral
see you soon bonbon (suave lvl 5): raises suave

Choice 5:
Mission complete: affection up
The pleasure was mine: neutral
I want to hang out more: affection up

Choice 6:
Thanks peanut: Neutral
Wink at her: affection up
Blow kiss: affection up (gives more)

July 10th afternoon
Peanut has an event at your house
Choice 1:
Go investigate: Neutral
Kick the trashcan: Event ends (Unlocks Kick the can)

Choice 2:
All three choices have the same effect

Choice 3:
Dumpster dive for the bracelet: Affection up
Pat peanut on the shoulder: ends event

Choice 4:
You are the cutest: affection up
I'm glad all this happened: neutral
I don't mind being your hero: affection up

Choice 5:
What's with all the dogs?: Neutral
How are you?: Neutral
Not bad: Affection up

Choice 6:
Working during summer vacation?: affection up
What happened to your projects?: affection up
Peanut the pirate: Affection up

Choice 7:
Grab the leash: Buff up, Affection up
Snap your fingers: Suave up, affection up
See tessa: Event ends

Choice 8:
She's a good girl: affection up
I was waiting for that to happen: affection up
You need hydration ASAP: affection up (gives the most, branching choice)

Choice 8 a:
Help her drink: Go to choice 8b
Hold the leashes: Go to choice 9

Choice 8 b:
Help dry: neutral
Point to: neutral

Choice 8 c:
Let us never speak of it again: Motivation up
You are... Completely wonderful: Suave up
Your boobs are incredible: Lucky up

Choice 9:
You're not a jinx: affection up
Twice.: affection up
My pleasure: affection up

July 11th evening
Peanut has an event in town
Choice 1:
Nice uniform: Affection up
At the circus?: Affection up
Peanuts were a snack: Affection up

Choice 2+3:
All three options leads to different choices all of which grant affection so pick the two that you like the most

Choice 4:
I have a car: Neutral
This is why you don't skip leg day: affection up
That's not what I want to do: Event ends

Choice 5:
Yeah 100% (buff level 5): Affection up
Better pass: Event ends

Choice 6:
All three optoons raise afffection

Choice 7:
what's the deal with the pizza thing?: Leads to branch 7 a
Stay quiet: Neutral (Special delivery achievement)

Choice 7 a:
Every option is pickable and grants affection (6 in total), this choice ends when you select "how much further to the top?"

Choice 8:
Thanks... it was fun: gain $100
You keep it: Affection up

Choice 9:
Go ahead please:
I have that effect on people: Event ends

Choice 10:
All three options raise affection

July 13th Afternoon
Peanut has an event at the mall

Choice 1:
High five: Grants the most affection
Hug: grants some affection
Smirk: neutral

Choice 2:
Every option but "Okay, I get the gist" adds more context

Choice 3+4:
Choice 3 just changes the options you get for choice 4, both of them are neutral so pick the ones you like the most.

Choice 5:
Holy heck. You ARE prepared.: Grants the most affection
I am both impressed and disturbed: Grants some affection
Is it weird that i'm a little turned on?: Grants some affection

Choice 6:
I have never been this relaxed in my life: Gives the most affection
I am full of sugar: Affection up
Not usually a fan of people touching my feet: neutral

Choice 7:
I'd love to ask you some personal questions: See choice 8 a
I've got a bunch of random questions: See choice 8 b
I'd love to kick back in silence: Skip to choice 9

Choice 8 a:
Every option grants affection, "let's chat about something else" brings you back to choice 7

Choice 8 b:
Every option grants affection, brings you back to choice 7 when you pick "favorite worldly possession"

Choice 9:
Give peanut the bill: affection down
Pay the bill ($100): neutral
Flirt you way out (suave lvl 5): Suave up

Choice 10:
My feet are ready for anything now: affection up
Do you want to take my car: Neutral

Choice 11:
Arcade: See arcade route
Beach: See beach route
I gotta run: affection down, event ends

Choice 1:
Maybe I can convince them: Continues the arcade route
Beach instead: Affection down, switches to beach route (locks arcade route)
Hit the road: Affection down, event ends

Choice 2,3,4:
All choices have the same effect

Choice 5:
Mio and I have fun: neutral
She's awesome: affection up
If you're thinking about trying to steal her: affection up

Choice 6:
You were okay: Affection up
I enjoyed every second of this: affection up
The manager thing was just a ruse...: Neutral

Choice 7:
Kind of you to say: Affection up
Mio's never been that charming and fun before: Raises affection the most
There are definitely benefits to my friendship: Neutral

Choice 8:
Let's hit the beach: Switches to beach route
Let's wrap it up: Affection down, ends event

Choice 1:
I love peaches: Affection up
I'm good: Neutral

Choice 2:
Yes: Affection up (grants more)
No: neutral
Don't answer: Affection up

Choice 3:
Get the disc: Affection up, causes choice 3 a
Hitting the waves: Affection up leads to arcade or finale
Let's just chill: Affection up leads to arcade or finale

Choice 3 a:
Both choices are neutral

Choice 3 b:
Hold still I'll help: leads to choice 3 c
Run into the ocean: Leads to arcade route or finale

Choice 3 c:
Gaze with desire: Affection up, leads to finale or arcade route (grants the most)
Lucky shell: Affection up, leads to finale or arcade route
Alls well that ends well: Affection up, leads to finale or arcade route
Choice 1
A useful marshmallow: Affection up
It sort of made my day: Affection up (gives the most)
It doesn't tend to work: affection up

Choice 2:
8/10: Grants some affection
5/10: Neutral
10/10: Grants the most affection (unlocks a perfect day achievement)

July 15th afternoon
Peanut has an event at the reed estate

Choice 1:
All three options grant affection

Choice 2:
All three options grant affection

Choice 3:
What did you do?: Raises affection
See you later: ends event

Choice 4:
Did you mess up the bushes?: neutral
Good luck: event ends

Choice 5:
I'll help: Affection up
say no more, best of luck: event ends

Unlocks Hedging your bets

July 16th morning
Peanut has a pizzeria event

Choice 1:
Luigi: Grants affection
Need... Pizza... Dying: Neutral
I was not expecting to see you in here: Affection up

Choice 2:
It's perfect: affection up
Not bad: affection up
This is going to tear a hole straight through me: neutral

Choice 3:
All three choices have the same effect

Choice 4:
All three options raise affection

Choice 5:
Nice weather today: neutral
Sneak out: Ends event

Choice 6:
save the pizza! (motivation lvl 1): affection up
Seduce (suave lvl 1): leads to choice 7 (Unlocks flirting with danger)
Run: ends event

Choice 7:
Mission successful: Suave up
Officer mommy: Suave up
It would be a privilege: neutral

Choice 8:
Your dreams?: Neutral
Not a stalker: Suave up
I'll never talk: suave up

Choice 9:
All choices raise affection

July 16th evening
Peanut has an event at your house

Choice 1:
All options give the same result

Choice 2:
All choices boost affection

Choice 3:
This seems extremely unusual: Raises affection
It's true then. The rich just don't party like we do: Affection up
I'm still not sure how you got me in here: neutral

Choice 4:
All three options are neutral

Choice 5:
I'm in: neutral
I'm out: ends event
I'm not leaving until I find out what caviar taste like: affection up

Choice 6:
Join the party:
Retreat: ends event

Choice 7:
All three raise affection

Choice 8:
All three options raise affection

Choice 9:
Play through the section involving serpent and bunny however you want, any choices with either of them have no impact on your relationship with Peanut

Choice 10:
I had a great time: Raises affection
It was... a thing.: Neutral
Kiss her on the cheek: Raises affection

Completing this even grants the party animal achievement

July 17th evening
Peanut has an event at the beach

Choice 1:
Definitely a date: Affection up
Bestie?: slightly increases affection
Kiss her: Affection up (grants kiss the girl achievement)

Choice 2:
I'm excited: Greatly increases affection (Gives the most)
Romantic sh*t I've ever seen: increases affection
Hit by a meteor: Increases affection

Choice 3:
Sounds amazing: Increases affection
I'm good: Neutral
MY head in your lap: Increases affection

Choice 4:
You can pick all 3
Perseid meteor: Increases affection
Tell my future: Moderately increases affection
Do you take all your dates here?: Increases affection

Got a wish ready?: Increases affection and moves the conversation forward

Choice 5:
Like a cosmic bouncer: Greatly Increases affection (gives the most)
Not after what I did: Increases affection
When you put it that way: Increases affection

Choice 6:
I love the way you speak: Considerably increases affection (gives the most)
Jupiter got rizz: Affection up
Jupiter's okay: Affection up

Choice 7:
Watch the stars: Neutral
Hold her hand: Affection up

Choice 8:
Yes: Increases affection (gives the most points)
Maybe you shouldn't: Neutral, Skip to step 15
Only if I can ask you one back: Increases affection

Choice 9:
...yes: neutral
I'm not sure: neutral
I'm enjoying this, but...: Neutral Skip to step 15

Choice 10:
I would be into it: Increases affection
Kiss her: Greatly increases affection (gives the most)
I don't want to hurt: Neutral Skip to step 15

Choice 11:
Let her make a move: neutral continues branch
Distract her: Skip to step 15

Choice 12:
Tell me: Neutral continues the branch
Look at Jupiter: Skip to step 15

Choice 13:
All choices are neutral and lead to a CG change

Choice 14:
Slide your hand into her shorts: Continues the scene (slightly more lewd)
Make out peanut: Continues the scene
Let her down easy: Skip to step 15

Choice 15:
I'll distract her: Tremendously increases affection
Run away: Neutral

July 19th afternoon
beach event

Choice 1:
The level 15 lucky stat will raise your luck by 1, but all options work

Choice 2:
Catch her (suave lvl 15): Increases affection and suave
Scoop her up (buff lvl 15): Increases affection and buff
Stand your ground: Neutral

Choice 3:
All choices raise affection

Choice 4:
Tell me what you're up to: Increases affection
Take it easy: ends event

Choice 5:
Looks fun: affection up
Cute uniform: affection up
Break trouble: neutral

Choice 6:
I don't want to keep you: ends event
I can drink em all: ends event
Would you like a bit of help?: affection up

Choice 7:
You keep it: Affection up
50/50: gain $50
You owe me a favor: affection up

July 22nd morning
Town event

Choice 1:
All three choices raise affection

Choice 2:
All three choices have the same result

Choice 3:
All three choices have the same result

Choice 4:
You can pick all three options and they all raise affection "sounds like you're having a blast" progresses the event

Choice 5:
All three choices raise affection

Choice 6:
All three choices have the same result

Choice 7:
Mind: tech savvy up, suave up
Body: Motivation up, body up
Spirit: neutral

Choice 8:
I have a cat: Neutral
Thank you: Affection up
Sounds like fun: Affection up

Choice 9:
All three options raise affection

July 24th morning
Mall event

Choice 1:
Every option has the same outcome

Choice 2:
In awe: suave +1
Buy lunch: suave +2
Stare: neutral

July 25th afternoon
Mall event

Choice 1:
Hello: Neutral
Listen: ends event
Leave: ends event

Choice 2:
Cowboy cobbler: Neutral
How's it going?: Neutral
Hug: affection up

Choice 3:
All three choices raise affection

July 26th night
House event
Choice 1:
Answer: Neutral
Decline: ends event

Choice 2:
Bad dream: Affection up, Skips choice 3
Most awkward booty call: Affection up
No phone. Bad peanut: event ends

Choice 3:
You weren't bothering me: Affection up
Not a booty call: Affection up
Goodnight: event ends

Choice 4:
I'm okay: neutral
A lot going on: neutral
Talk to you later: Ends event

Choice 5:
It's raining cats and dogs: Increases affection
That's reckless: Moderately increases affection (gives more)
Please stay home: Event ends

Choice 6:
Both choices have the same result

Choice 7:
You're wet: Raises affection
Took you long enough: Increases affection
I adore you so much: Affection boost (gives the most)

Choice 8:
I'll take a look: Raises affection
Cat girl costume: Neutral
Birthday suit: Neutral

Choice 9:
Orange is your color: Increases affection
You look fantastic: Greatly increases affection
A bit big on you: increases affection

Choice 10:
I cry at dog movies: slightly increases affection
The world could use more of it: Raises affection
We simply love: Raises affection

Choice 11:
All options have the same outcome

Choice 12:
All options have the same outcome

Choice 13:
You can pick every option to raise affection. "I've got a dangerous road ahead i'm not sure I can handle..." ends this choice

Choice 14:
Both choices are neutral but why would you ever say no to Peanut hugs?

Choice 15:
All three options raise affection by roughly the same amount

Choice 16:
Perfectly logical: Slightly raises affection
You're adorable: Raises affection (gives the most)
Sorry, I blanked: Slightly raises affection

Choice 17:
I object: Raises affection
It's a passion of mine: Slightly raises affection
Utterly magnificent: Raises affection branches into 17 a

Choice 17 a:
All three choices have the same outcome

Choice 18:
Bring it on: raises affection
Keep this PC: Raises affection by a fair amount (gives the most)
I'd rather do something else: neutral, skip to choice 23

Choice 19:
Over the clothes: raises affection skip to choice 21
Gotten to know people well: raises affection
I chicken out: neutral skip to choice 21

Choice 20:
In more ways than one: large affection boost (gives the most)
Warm up: Raises affection
Not even close: neutral

Choice 21:
It's awesome: Considerable affection boost
Definitely unexpected: Moderate affection boost
Out of left field: Neutral

Choice 22:
All three options are pickable and have mini dialogue branches
"sexy university tv shows" give the most for the fantasy branch
"I have no special talents" gives the most affection for the top or bottom branch
All three choices give equal affection in the flirting branch
The "comes rather quickly" branch grants no affection for any choice
"I think you should ask a question now" progresses the event

Choice 23:
Something I did?: Neutral
Someone else: Neutral
Did I... hurt you in some way: raises affection

Choice 24:
Go on: neutral skip to 25
I think so: neutral skip to 25
I mostly did stuff to you: branches into 24 a

Choice 24 a:
That makes two of us: Raises affection
I'm glad you enjoyed it: Slightly raises affection
I lost control of myself: Raises affection

Choice 25:
We're cool: Raises affection
A bit out of character: Neutral
I think you'll feel better: Neutral

Choice 26:
I like every version: Decently raises affection (gives the most)
It was flattering: raises affection
I forgive you: raises affection

Choice 27:
Goodnight: Neutral
Kiss: raises affection
Make love: boost affection, special CG

Choice 28:
You can pick all three options which all raise affection
"Climb on top and bring her to climax" ends the event

If the conditions for the standard good ending are met by the 31st (No girls died and you didn't do anything evil) and you finished all of Peanut's dates she will show up at the airport to go home with you. You can of course turn her down if you wish to see the ending of another girl.

Picking Peanut unlocks the I choose you achievement