Search of Genres for "action"

Nuclear Dragon
Number One Zombie Wife
Nurarihyon no Mago
Nuwu
O-ri-ga-mi
O.V.E.R.L.O.A.D One Day… I Am a Villainess
Ochita Kuroi Yuusha no Densetsu
Ochite Kita Naga to Horobiyuku Majo no Kuni
Oda Nobuna no Yabou
Oda Nobuna no Yabou Gaiden – Jakigan Ryuu Masamune
Office Worker's Immortal Dungeon
Oh My Ice Goddess
Oi, Hazure Sukiru da to Omowareteita "Chiito Koodo Soosa" ga Bakemono Sugiran da ga
Okami Wa Nemuranai
Okay, Let's Become the Demon King
Okitara 20nen Nandesukedo! Akuyaku Reijo no Sono Ato no Sono Ato
Okoborehime to Entaku no Kishi
Old Maid
Omni Genius
Omni-Magician
Omnia wo Suberumono
Omnipotent Overlord
Omnipotent Sage
Omniscient Reader's Viewpoint
Once Upon A Time, There Was A Spirit Sword Mountain
One Man Army
One piece Bounty System
One Piece Enhancement
one piece invincible
One Piece Shura
One Piece Talent System
One Piece – Thundergod Marine
One Piece: The Soul Purchasing Pirate
One Planet for Everyone! Building Science and Technology Civilization at the Beginning
One Punch of Justice
One Sword to Immortality
One Turn Kill of the Dark Partisan
Ongaku no Shinigami
Online Game: Evil Dragon Against The Heaven
Only I am not attacked in a world overflowing with zombies
Only I Shall Be Immortal
Only I Who Got The Initial Job As Demon King
Onrain (Online – The Novel)
Open a Clinic to Cultivate Myself
Ore Dake Kaereru Kurasu Teni
Ore ga Heroine wo Tasukesugite Sekai ga Little Apocalypse!
Ore no Isekai Shimai ga Jichou Shinai!
Ore no Kioku ga nai Isekai no Danjon to Maho no Gakko
Ore no Ongaeshi: High Spec Murazukuri
Ore, Doubutsu ya Mamono to Hanaseru n desu