Could the problem come when you reject him pointing at your partner? There are two lines there, asair. First "Will not lie, I did think about it but I am with someone else" and second - "No, I am not interested."

I chose second straight away, and did not run into any problems. (Well, he did insist I was asking him about his private life, but that was a clear bug). Maybe if you chose the first answer, the game labelled you as "thinking", even if you say "no" at the end.

Not saying it's good, but kind of fits his general kink?