I'm bored

Peerless dad, solo leveling, the legend of the northern blade

Here ya go hun. Have fun (●'◡'●)ﾉ

Murim Login
Tomb raider king
Omniscient Readers viewpoint
Nano machine
SSS class suicide hunter
Kill the hero
Beginning after the End
Legend of the northern blade
Gamers
Return of the frozen Hero
Player who can't level up
Doctor rebirth
Max level retuner
Poison Dragon: Legend of Asura
The Tutorial tower of an advanced player
The beginning after the end
Reverse Villain
Dungeon Reset
Solo leveling
The max level hero has returned
The Descent of Demonic Master
Eleceed
Noblesse
Ranker who lives a second life
Leveling up only by eating
Berserk of the Gluttony
Trapped in a webnovel as a good for nothing
Arcana Fantasy
Mercenary Enrollment
Weak Hero
Study Group
Lightning degree
The undefeated swordsman
Viral Hit
Peerless Dad
Path of Shaman
Return to Player
Trash of counts family
Gangnam Dokkaebi
Villain to kill
Polarity
Other worldly sword Kings survival record
Return Survival
True Education
Limit Breaker
Arcane Sniper
The Boxer
The Lords coins aren't decreasing
Solo spell caster
Again my life
Medical Return
OOPARTS
The live

i have a couple suggestions but i feel like you've probably seen these already since a lotta them are pretty popular (also i'm realising someone above already included a lot of these so you can just take these as their links LMAO)

- https://www.mangago.me/read-manga/dungeon_reset/ (there isn't even a girl character in this. but if there was, im sure she'd be written really well)

- https://www.mangago.me/read-manga/path_of_the_shaman/ (THIS ONE IS SO GOOD AND THE MC IS OP BUT NOT IRRITATINGLY 2D! sorry i simp after him so hard)

- https://www.mangago.me/read-manga/the_constellation_that_returned_from_hell/ (just op mc + his pet rock)

- https://www.mangago.me/read-manga/return_of_the_flowery_mountain_sect/ (no romance at all!!)

- https://www.mangago.me/read-manga/limit_breaker/ (all the girls in this manhwa have zero romantic interest in mc)

- https://www.mangago.me/read-manga/mashle_magic_and_muscles/ (there is one fangirl, but she's played off as slapstick the same way the entire supporting cast and even the op mc are)

- https://www.mangago.me/read-manga/to_a_new_life/ (yooo this so far seems SO good, but it only has six chapters rn if you're fine with that)

- https://www.mangago.me/read-manga/murim_login/ (a hidden gem. mc takes time to develop his character + backbone, tho. so idk if this fits in the 'op' energy you're looking for)

- https://www.mangago.me/read-manga/return_of_the_frozen_player/ (all of the girls introduced are clearly not going down a harem route, and all of this is action)

- honestly one punch man. one punch man's female characters have zero romantic interest in mc

- https://www.mangago.me/read-manga/chainsaw_man/ (the girls in chainsaw man are really well developed)

- https://www.mangago.me/read-manga/golden_kamui/ (haven't finished reading this, so tbh idk if there's any romantic interest in the future, but so far it's just grandpa energy of a mc + little sidekick you know)

- https://www.mangago.me/read-manga/gokurakugai_sanbandori_no_ken/ the girl is so badass in this >:)

- https://www.mangago.me/read-manga/mouryou_shoujo/ (this might not be the type of genre you're looking for ngl, but it's definitely a good read)

- https://www.mangago.me/read-manga/lovelock_of_majestic_war/ (generic shounen plot, but not bad)

- https://www.mangago.me/read-manga/weak_hero/

- https://www.mangago.me/read-manga/yuukoku_no_moriarty/

- https://www.mangago.me/read-manga/study_group/ (honestly, there's one girl in here who's so badass im kinda in love with her)

- https://www.mangago.me/read-manga/please_have_a_meal/ (this one's cute tbh)

- https://www.mangago.me/read-manga/worn_and_torn_newbie/ (uh there is kinda an antagonistic girl who gains a crush on his alter ego, but it's not annoying imo, it just moves the plot and plays slapstick rather than becomes an actual thing)

- https://www.mangago.me/read-manga/global_examination/ (tho, this is a bl just to let you know. the action in this is impeccable tho)

- https://www.mangago.me/read-manga/arcane_sniper/ (uh idk if this will go down a harem route. so far it hasn't)

- https://www.mangago.me/read-manga/bullet_6mm/ (tho, the translations of this seemed to be dropped)

- https://www.mangago.me/read-manga/dead_mount_death_play/

- https://www.mangago.me/read-manga/the_boxer/ (uh tbh this feels more like,,, a drama/tragedy than action despite it being centered around it)

- https://www.mangago.me/read-manga/return_to_player/ (there seems to be a FL who might,,, have,,, idk possessive tendencies, but it's easy to ignore as nothing more than just a character undertone)

- https://www.mangago.me/read-manga/try_me_again_if_you_dare/ (idek. comedy?)