I actually kind of like that they didn't end up together (at least for now, maybe in the side stories they will) but the fact that even though she fell in love with him, she still stuck with her main goal of betraying him to escape. Sometimes manwhas derail once the mc falls in love but I'm glad this one didn't, because even if she did kill that piece of shit, she doesn't deserve to be in jail!
I kinda wish that Mamoru stood up to his friends when the one was clearly disrespecting Tsubaki to her and his face. Like c'mon man, that's not cool...