Horimiya is a true romance manga.

Horimiya doesn't have the typical romance drama. Some people like the drama, but I'm not the biggest fan of it. A lot of the drama in romance is just there to pad the run time in my opinion. Oh, you think those two are finally getting together? Here is a new character that messes it all up. They finally start dating? Oh, the father doesn't approve and they have to break up, adding 50 more chapters. Horimiya doesn't have that.

It's a story of two people who love each other. Hori, the popular girl, takes care of her little brother. Miyamura doesn't have the tattoos and piercings because he is edgy, he got them because he's stupid. He's a loveable idiot.

Once they get together, they stay together, and the rest of the show is just them being together. It's similar to Tonikawa in that regard.