I Love You Since We're Still A Child

A normal girl who's a highschool student is in love with her childhood friend! He is her classmaste, her roommate and their school heart-throb, Adonis Proteus Adler. She has been waiting for the festival to come so that she can confess her feelings for her first love, but... "O-ohh... Congratulations for the both of you!" 'Why? H-how could you do this to me?'