To start this small ingame story quicktravel to Fairlane Hill Estates (south of Diamond City), turn to the left and follow the street to the next knocked down tree. Head directly again to the left, climb up the slope and you'll find a locked cage with the dog Teddy in it.

You should make a quicksave now. Opening the cage (advanced lock) will spawn two raiders, attacking you. Make sure just to kill the raiders instead of Teddy, who is trying to help you while the fight.

After defeating the raiders follow Teddy. He will lead you to the hidden vendor Eleanor. Beside she is talking to you and you can trade some stuff, maybe Dogmeat (if he's your companion at this time) will become a friend to Teddy. Then head inside Eleanor's trailer and you'll find a note about Bosco on the table. But where is he?

Look out for the (Don Bosco) D.B. Tech Highschool in the east of the map. Enter the building, fight your way down to the deepest level and you'll find the raider-leader Bosco on the end of a wooden stage. Kill him and you're now owing the unique "Mascot Head".
But that's not all. Enter the second floor of the Highschool and search for a room with lockers on the northern side of the building. On top of one locker you can also find the unique D.B. Tech Varsity Uniform.

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