Sumarin Kanojo-tachi

Satoru Hasegawa, a young real estate agent, lives together with his equally young wife, Aya, and their daughter. Five years into their marriage, he's not particularly dissatisfied with anything, but he's got a secret that he can't tell a soul! Satoru is helpless before Sayaka, an escort, and Eri, his boss at work, and he's been carrying on lively affairs with both of them. But then he meets a woman with the faint aura of first love... This is a romantic suspense story about a man who can't tear his eyes away from that sweet but dangerous trap.

(Source: Manga Box)