カノジョの妹とキスをした。

[DeepL Translation - needs review] Volume 1: Introduction:. You can't show this to your sister, can you? My girlfriend's estranged sister is now my own sister-in-law! The day I was finally able to hold hands with Haruka, the first girlfriend in my life, after one month of dating, my parents remarried and I had a sister-in-law who looked exactly like Haruka. Her name is Shigure. No wonder they look so much alike. Shigure was my twin sister who was separated from Haruka due to family reasons. ...