Ishoku Bitch to Yarisaa Seikatsu

Welcome to the Do-It-Club, where only perverts gather!! This club with the motto "Let's get along and be filthy together" that a new college student, Hiroshi Hirose, is checking out lightly, is in an outrageous club filled with girls who love sex!!
(Source: Coolmic)
Includes the extra chapters:
1. Uwakishou Kanojo (浮気性彼女, Filthy Girlfriend)
2. Cosplay Hitozuma Ai (コスプレ人妻あい, A Married Cosplayer, Ai)
3. Seiryaku Kekkon (性略結婚, Sex Marriage)