Doesn't he also get embarrassed when you immediately take him up on his offer?
Like; "Uhh... You're going to beg me for it later instead! Goodbye!" or something along those lines?
He does. On my playthrough as a tiefling I chose that option. I mean, I was probably going to go to Hell anyways, may as well get something out of it.
It does seem he's triggered after you try one of the options to rid yourself of the tadpole. It doesn't matter how many nights you rest, he won't show up til you explore one of the ways to get it out of your head. For that matter, you could try none of them and not even see him on your entire run.
