Years ago I read a manga (not sure if it was H or non-H), and I cannot remember for the life of me what it was called. I remember that it was about a guy who kept getting roped into cheating on his girlfriend with another girl who was a quick change artist, so they would start having relations in various places/times. One particular event that sticks out for me was when the cheating girl started relations in the living room when the girlfriend was cooking in the kitchen for example, and whenever the girlfriend walked out to check on them the cheating girl quickly dressed herself and the guy at the same time like nothing happened. My Google-fu has failed me in this search thus far, so any help would be greatly appreciated.