Responses
Gintama (there are some ships but the author didn't make any official cannon, there's little romance anyway)
Beelzebub
Boku no Hero Academia (stay away from the fandom if you don't wang ghe romance)
Bungou Stray Dogs
One Piece (very long lmao)
Ansatsu Kyoushitsu
any action mangas without romance? i prefer the ones with many chapters already. thanks :****