That's a very interesting point. Would that mean that they would lose the bet? It probably would in Hinako's case if she was saying she liked someone else (instead of Hirose) while doing the deed, but we don't know what would happen in Hirose's case since we don't know the full extent of the actual terms of his bet with the witch. Nonetheless, winning the bet, at least on Hinako's part, is not predicated on Hirose having mutual feelings for her, only that her feelings for him do not waver. He could end up with someone else but if her feelings don't change, she will still win the bet.I guess it would be really awkward if one of them watched the other masturbating, but they were jerking to someone else.
Same here, particularly since we've already seen a potential rival in the form of the Class Vice President. And there's also the possibility that either Hinako or Hirose would enter into a fake relationship with a 3rd party to disguise the fact that they had feelings for each other. The complications seem endless......kinda hope the story not going to turn into slight NTR given the premise.