I had a theory that Seonho was going to be the type of character who stays quiet when he needs to speak up.
So he didn’t need to be unnecessarily hurt the first time he had sex with Won if he’d actually answered the question.
Won is a child in an adult body, so he “listens” if you talk to him.
Seonho should be using that to his advantage instead of caving in to his yandere “friend”.
His life might just be easier if he did that.