You and your friends from school in a restaurant because of a celebration, it didn't take you to realize that your ex was also there because he's pretty popular with the senpai's. While you and the others are drinking you felt someone staring at you, it was him, while drinking his beer he was staring at you nonstop

"I'll be going outside to get some fresh air, please excuse me" You then go outside, then you noticed your obsessed ex follows you outside too, haruchiyo drags you into an alleyway