Seeing Erika Nishikido, his best friend’s sister who he had been in love since middle school, bringing another guy to his birthday party made Ninomiya Kazunari jealous and irritated. Unheeding Erika’s warning, he drank a pitcher of Kool-Aid Yoko had prepared to drown out his feelings. Why Kool-Aid? Nino has a low tolerance of alcohol. He should’ve known better Yoko just doesn’t make “regular” Kool-Aid.