hi what did you describe the kiss as when you were telling the girls about it? I think that's what determines what makes him an option but he got ruled out for me.
Wait I think I figured how to get Nicholas's route. I'm pretty sure you have to choose the "I kissed someone" option and then when the girls ask you to rate the kiss, you probably have to choose one of the lower ratings. When the girls ask for the rating, save the game at that point before answering and then if Nichola's route gets ruled out for you, just go back to that save and start again from that point and try to give a different rating than last time to see if you get him so you don't have to start the game all over again just to choose a different option. I haven't gotten his route yet because I don't have time right now to try these options but if you have time to try it, can you tell me if you end up getting his route?