most fury VNs have all the same vanilla LIs that have boring personalities, it's good to see a bad boy for a change
well, she was treating him like he was her boyfriend and it irritated him...
but I see your point if a guy treats my friends like this in real life I would get mad too, but since it's a game I found it kinda that he is so nonchalant and no nonsense towards girls and so warm with our MC, but I guess that's just me.