Tsunagaranai Keitai Denwa -Tadaima Hoka no Otoko to Mechamecha Sex Chuu | 繋がらない携帯電話 －ただいま他の男とめちゃめちゃセックス中－

The two were happy. Nothing had uneasiness. Until the engagement is decided.

To Protagonist Takahashi, there was only one anxiety. It is a weakness of liquor to Ukai Nanako. It likes to drink though it is weak. Then that much though it is still nice, the memory of the back and forth is eliminated when getting dizzy. Of course the two knew it and were careful enough. The friend from college student days watched it at the seats of the drinking session so that there was not "a mistake".

However after deciding the engagement, it is later... the letter with no sender's name written on it reaches the origin of Protagonist.

[Your fiance is having an affair it. It is made drinking sake in the place in which it doesn't know, it is done to be nice. I seem to enjoy a man excluding you because it does the gotten dizzy pretense recently. Still do it marry?]

It was to laugh down, but one and two idea appear if i reconsider it. No, surely such...