I think Jaeha called Taegun a used rag in an earlier chapter...
It wouldn't surprise me if Taegun got mind-whammied to think the guy he was sleeping with was Jaeha, only to be horrified at the reality afterward. Probably more than once, given how big of a scumbag Jaeha is.
I keep forgetting what his power is. I hadn’t thought about that, but it’s a very big possibility that’s what he did. When I was translating the chapter there’s a flashback where Taegun asks him why he did that and him that he tells him he’s a bit of the boring type. The implications are terrifying but I can totally see Jaeha pulling that kind of sick move for his amusement.
He deserves to die slowly and painfully in a dungeon.
SPOILERS FOR CHAPTER 51:
Last chapter there was a random scene Taegun remembered where it showed him in bed with some unknown guy.
Also last chapter he threatened Jaeha to stay away from Eunsung.
So this chapter Taengunnis visibly shaken by his interaction with Jaeha and is unstable. There’s another flashback where he tells Jaeha “why did you do that?” And Jaeha responded with “you’re a bit boring”. That, coupled with the fact that Taegun desperately doesn’t want Eunsung to find out and even thinks “what would Eunsung think if he found out?” I get the feeling Jaeha pushed Teagun to sleep with other guys for his own amusement.
Originally from that random flashback, I thought Taegun had slept around for money at some point, but now it seems it was Jaeha that made him do it.
If true, Jaeha deserves to be eaten slowly by a dungeon monster.