Cute romcom anime, always had a soft spot for these ecchi romcoms. Expected something silly and ecchi, got something silly and ecchi but also well made, with a good set up for a romance between the characters, and a unique concept.
All of these literally just translate to young boy/girl and adult man/woman. Its no different than going to the store and seeing the Young Adult section at a bookstore or some shit.
It means absolutely nothing about the genre as a whole, as an example. all of these are seinen.