Spoiler explanation
well from what I understand is what the blondie @sswhole was saying was that Taehwan was no better than him and that he was using Yeonwu, Yeonwu hears this and the gears pretty much start turning for the both of them. Taehwan in denial does try to suppress his negative feeling (guilt this time) how he usually does with sex... but in truth, he knows he's no better than him and it's constantly ringing in his head in the monologue and Yeonwu finally tells him no cause finally realizes that too. In all honesty, I wished he figured this out on his own instead of the blond @sswhole telling him instead making it all the more heartbreaking in my opinion.
wtf the last raw ┑( ̄Д  ̄)┍ gonna cry in my bed