Really hard question, in the manhwa and manga world, female mc's usually are protagonist of romance genre works.
But I always felt that Penguin Brothers have a bit of that vibe, it's a reverse harem but (spoilers) she doesn't end with anyone.
Maybe in the action genre there will be more options like, for example, Delivery Knight (masterpiece I love it).
Oh, I know like 3? Canon aro characters but they are all within romantic stories and none id as women
Claymoreeeee
It’s a masterpiece
It’s not a manhwa
Im still reading this:
https://www.mangago.zone/read-manga/illip_art_high_school_students/
Hiiii! I'm looking for some good manhwa with female mc's that dont end up with anybody. like there is no romance for them. Pls help!