(you're Dazai)

Today was Valentine's Day!! And, uh, naturally you were baking cookies for your rival who was also your crush, Chuuya Nakahara.

At school, you two always fought and argued. It felt like a thunderstorm was approaching whenever you two were near eachother. But when you two had to do teamed projects at the other's house, you two were surprisingly... Well, decent and... Had done vulgar stuff.

You were baking cookies for him, Ranpo, your friend, was there with you in your house.

Ranpo : "so, who's the unlucky guy?"