- Hikikomori (20)
- Homunculus (12)
- Honest Protagonist (192)
- Hospital (55)
- Hot-blooded Protagonist (109)
- Human Experimentation (191)
- Human Weapon (46)
- Human-Nonhuman Relationship (643)
- Humanoid Protagonist (270)
- Hunters (396)
- Hypnotism (82)
- Identity Crisis (61)
- Imaginary Friend (5)
- Immortals (957)
- Imperial Harem (269)
- Incest (527)
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- Indecisive Protagonist (31)
- Industrialization (178)
- Inferiority Complex (145)
- Inheritance (133)
- Inscriptions (21)
- Insects (108)
- Interconnected Storylines (50)
- Interdimensional Travel (377)
- Introverted Protagonist (112)
- Investigations (167)
- Invisibility (12)
- Jack of All Trades (166)
- Jealousy (513)
- Jiangshi (12)
- Jobless Class (10)
- JSDF (6)
- Kidnappings (197)
- Kind Love Interests (588)
- Kingdom Building (941)
- Kingdoms (839)
- Knights (756)
- Kuudere (71)
- Lack of Common Sense (352)
- Language Barrier (29)
- Late Romance (493)
- Lawyers (76)
- Lazy Protagonist (327)
- Leadership (432)
- Legendary Artifacts (126)
- Legends (79)
- Level System (1152)
- Library (37)
- Limited Lifespan (65)