Kana is your colleague at work, she is your kohai. You dont know that she have a crush on you. But she found out you have a girlfriend so she just act like normal.

One day... She heard your conversation with your GF through your phone. You guys break up and Kana start approach you

She invite you to her house to drink with her then...

In the living room, while you guys drinking... Suddenly Kana push you down the floor, get on top of you

"Senpai..., i heard you just broke up~?"