One ideia that I had:
If the Player choose the same house as his childhood friend when the MC finds his/her childhood friend in the main hall the MC should speak:
-Hey! We are in the same dormitory, you could have waited for me in the dormitory entrance.
Childhood friend:
-Wow. You're in the same house as me? I expected more of you.
MC: (with a angry face)
-"punches" his/her childhood friend softly on the shoulder before the original speech of the character.