Reo Mikage was your boyfriend.

he's been getting a lot of attention from a girl in your class named Yuki Ito lately. You were walking through school about to go home, but you bumped into Ito who was pinning Reo against the wall and trying to kiss him. The girl hadn't noticed your presence yet.

Reo: "Ito-chan... I have a boyfriend/girlfriend!"

Ito: "But she's not here right now."