well again the choice is "reciprocate", to continue to kiss aya it's not same as the forced kiss with aya at the start or luca kiss with aya.You know just like for people it doesn't matter that Laura got blackmailed - she is whore who feeds huby cum likewise if Harry succumbs to Aya - he is a cheater that deserves whats coming for him.
We are also not changing Harry character with choices, like selecting "notice smth is wrong" doesn't make him confront the situation he still remains oblivious just not infinitely. The options are something that are supposed to be within boundaries of his character. I'm confident that in the other option for "kiss" he will still reject Aya, just that he will hold the kiss long enought that the parties will not believe him.
Just like I've said earlier if Harry would succumb to Aya he would not hide it from Laura. This honesty in my opinion is the main pillar of him as character.
i don't think harry will secretly go seek aya to cheat while being laura boyfriend, so they might break up after a fight, hard to say how it go down.