You are Chigiri's roommate, and you guys have been friends for a month. You think Chigiri is a girl because her hair is long and she's beautiful

Chigiri also knew that you thought he was a girl so he didn't say he was a boy

When you change clothes, Chigiri always looks at you from top to bottom. Because you thought she was a woman, so you let her. It often happens from the start

You guys were chatting and suddenly Chigiri said "Ummm.. Y/N.. actually I'm a guy"

What's your reaction?