I read this about 3 years ago so details are kinda blurry. What I remember is that it was a B/W bl manga. Both the MC and ML were playboys (I don't remember if this scene was part of this manga or not but at the start we see a sandwich sex scene of MC, ML and a girl in between). They get curious one day and ML (seme) and MC (uke) sleep together. MC starts kinda falling for the ML but ML is still the same playboy. I think he even encouraged MC to fuck girls too. I'm guessing ML never thought MC would give his ass to any other guy. MC reached a point where he just went out at night and saw some hooligans on the street and literally paid them to fuck him. They all took turns and fucked MC. ML found him and really starts regretting it. Then they sort things out and start dating.