
There aren't that many chapters out yet, and the seme's level of sexuality hasn't really been mentioned. He's having mental beef with the uke because he thinks uke is a player since he kissed seme back in the army. I think uke was recently engaged to a woman, but that broke off I think? but yeah, they haven't really shown whether he was prolific in his sex life.

When he first sleeps with Hyung he thinks to himself he mever had the desire to roll around naked with someone until now and that he “almost” slept with a woman once but “the weight that settled on top of him was a little different than he remembered so he pulled away and didn’t feel the value of trying again after that”. This is from novel 2 page 25

I posted the link to the novel awhile ago, but the Korean novel is available on google playstore. That being said, it is NOT free but its only a couple bucks per book.
https://play.google.com/store/books/series?id=ZR5GHAAAABAiAM
Is the seme a playboy who slept around before meeting the uke?