Goofy take. It's always an awkward, difficult situation when you're dating someone, and their friend starts coming onto you. Bringing it up feels dangerous, because they're the friend, they've been known by your girlfriend a lot longer than you have, it feels like jealous boyfriend shit or something. Furthermore, it's especially rough when they're sixty feet tall. Certainly the noble thing to do is tell them no firmly, but what if that pisses them off? Chicks can froth at the mouth IRL when you reject them, so what about a giantess? It's not outside the realm of possibility that the MC would acquiesce to her advances just to hope they wouldn't happen again for fear that rejection will piss her off.
Also, what a take, "he cheated on the first day of the relationship, he must die". There's an acceptable time to kill your partner for cheating, it's 10 years into a marriage and finding out the whole time she's been banging the mailman and none of the kids are yours. It's not the first day you started dating after the first day you met. At that point you just throw your hands up in the air and go "OK fine whatever, but get out of my house".