1. So? His dad himself encourages him to find a mate1. He himself said that he's still not able to beat his dad.
2. His pupils are MUCH younger than him. No matter they have grown up, in his mind they're still his 'children'. See Ch. 11 p. 30.
2. So what's the point of this manga then? "Just-Blue-Ball-The-Manga" What's the point of every main female character clearly having some form of love for the MC? Because It's a creepy and disgusting age gap? They are already an adult so what? It's the MC that needs to hold his ass together. if anything I hope his pupils find someone else and let the MC grow old single with the mindset of a hermit
I realize it's not a romance focus manga, but if the premise is about one guy with a bunch of attractive girls, then it's valid to get frustrated at how spineless the MC is, it's like Rental Kanojo but with shonen battle