I'm a librarian who loves anime, manga, and reading a wide variety of genres.
It won't be out until 2019 (!), but apparently Boyfriend Dungeon is supposed to be a cross between a dungeon crawler and a dating sim. You can defeat enemies and date your weapon.
I've only read a couple articles on it, and none of them have mentioned Soul Eater, but they really should. It's a series (manga, anime) set in a world where two or more people (mostly pairs) team up to collect the souls of evil humans and witches. At least one person in each team has the ability to transform into a weapon that another person in the team uses. The main characters are a girl and her scythe partner.
It'll be interesting to see how Boyfriend Dungeon works out. It'd be nice if it were a little further along and actually had a release date.