The way MC acts is very unmanly, or even a "beta-like" behavior... I can totally understand him not wanting to kiss/fuck those girls. (It's just common sense to do those things w/ a person you know well, and towards who you have feelings for..)
That's not the point here. The point is HOW he does the rejection. He just keeps screaming/jumping/running like a child, or a person w/ autism (yeah, he's not an adult quite yet, but he's not a child either)..
That is the point here. He could be very confident (even just a little bit at least), and not jump around like some rabbit (or any other prey-animal), and just take it slow, and use rational reasoning towards those bitches (regardless if it would work or not).
Once again. Very unmanly, beta-male japanese teenager... Oh boy, where have we seen this before? (rhetorical question)
I'm not saying his behavior is unnatural, or impossible, or not even very rare in a situation like that.
I'm just saying that readers hate this trope. Still these idiotic authors keep creating these insecure "men" in their stories as main characters. It's just so exhausting to see "one of these"