The problem is Martin doesn't take himself seriously, and lacks in self confidence. Lets leave aside his mom's occupation for this. He came all the way from California for a gf who ended up leaving him, leaving him alone in a new place. His first major interest in the QC story reciprocated interest but rejected him based on personal issues (understandable) which were later solved (more like progress made) but then Angus came along. His relationship with Dora was not of any effort on his part, he was oblivious about her feelings until she kissed him on the rooftop.
Tbh, I would be insulted if someone described me as a pushover and his partial acceptance of the term shows his lack of confidence which is why I believe she laughed at him after the makeout statement. And why wouldn't she? It is creepy to make such a statement when you have already set yourself up like he did earlier in the party, it makes you seem desperate when you have admitted your timidity.
This is not me saying he needs to become the "alpha male" that certain people on a certain website seem to glorify, but he needs to start believing he is worthy of a relationship before he can attempt at making one. Obviously, we know he admitted to Tai before the party that he doesn't even know what he wants right now. His attitude is that by being laid back he will just fall into a long lasting and rewarding relationship, that just doesn't really happen and he should have taken a lesson when his relationship with Dora failed, but didn't.
That is it for me over analyzing a webcomic. I am open to changing my views on things if anyone disagrees with this assessment.