I was also a little slow about women at age 26 (even though I was on a second marriage at 26).
So I get him being unaware for a month or two.
But I am beginning to wonder if Japanese men are just completely idiotic when it comes to other humans even existing. I mean, a trope is one thing, but... if the story and the people in it are all developing, and learning amd growing, but the MC is still mentally an Eleven-year-old?
I mean... at that point it's not a trope, but a severe learning disability.