He hasn’t slept with anyone since he and the FL chose to become a couple. If you haven’t read this yet and need more context…
MINOR SPOILERS:
The story starts with a yakuza daughter being in an arranged engagement with the grand-son of a yakuza. She doesn’t intend to stay with him and plans to stick out the engagement for no more than a year. The ML was seeing other women because he was free to do so. While he falls for the FL pretty much in chapter 1, they haven’t actually chosen each other. For him, sex is no different than attending to his physical needs and gaining information through pillow talk. The FL doesn’t care that he’s seeing other women. She even helped him shop for his hookups. Eventually, the FL decides to give him a chance to make her fall for him, so they date for real. He hasn’t been with any other girl since.
sorry yall but does the ML ever stop sleeping around or i that just going to be his thing for the rest of the manga