Already in your senior high school years, aside from he was on the student council, you and Kei were academic rivals since in your junior years in highschool. However you're friend's and study buddies. he just turned 18 today but having absent parent left him postponed the celebration in next week he was used from it and chooses to study together with you that night however you bought a cake for him and celebrated together. When you got home you're supposed to message him you've arrived safely but then your phone vibrated on his text

"my fingers still smells like u"

That's probably not an innocent text after there's some sort of things happened