It was probably only one chapter in a manga. There was a debt collector who slept with the young man who had this debt. He was a student and also had an affair with a married man. The most important thing is that he only pretended that he didn't have money he just wanted some thrill and excitement. Eventually the debt collector resigned from his job and advised the student to stop selling his body, They met after some time again and he was a plumber. I was sure it was work by Ogura Muku because the atwork was very delicate but I could't find it. Please help me. I have already searched on baka updates by different debt related categories.

maybe Hatsukoi (Kakine).??