
I think you’re confused, in some BL stories the top is essentially straight before he meets the bottom like in Codename Anastasia where the Top…..
SPOILERS
Literally fucks 3 different women unprotected, but somehow he has no STD from those encounters and no unplanned children? Like… this is definitely not the first time he’s been fucking people so…. Where are the children and STDs?

Oh. I see.
(And yes, I have read Codename)
But I was just referring to BLs. Where (like this one), the top, or the bottom, whomever is promiscuous, would get STDs.
We're assuming , ofc, that as straight or bi men, then yes, ofc they can get someone pregnant, if they don it bareback. Most of the time, it seems that the use of contraceptives isn't mentioned. We don't know if the women are on BCs or not.
Han Seo In.....Even though I loves his appearance, I really detest his personality. Like how he avoided contracting any STDs, by participating in those orgies? Oh, right he does not engage in penetration, if I'm not wrong. Well I don't want him to be the ML when we have Taegun hyung ♡