Rimuru

Biodata

Feature	Information
Name	Rimuru Tempest (利姆露) 1
Alias(es)	White Knight; Leviathan; Lord of Blue; Blue Lecturer 26 76 166
Species/Race	Physically a slime; the Tempest lineage is identified as a human–Phantasmal Species hybrid line 9 48
Gender	Male
Affiliation	Tempest Family; Clock Tower; Altrouge's faction; an Academy City dark-side organization 27 117 222
Occupation/Role	Clock Tower professor; Lord of Blue; Head of the Department of Modern Magecraft; leader of a dark-side organization 16 117 122 222
Status	Active 235
First Appearance	Chapter 1 1

Power Progression

Stage / Realm / Level	Chapter	Notes
Clock Tower professor / Blue Lecturer	6, 26	The Faculty Council reinstates him as a professor; he is subsequently known as the influential Blue Lecturer. 6 26
White Knight and blood-derived power	27, 76	He joins Altrouge's faction in exchange for her protection and assistance, gaining power from her blood; he later manifests blood-bat wings and the power of a True Ancestor. 27 76
Lord of Blue	117	Rimuru becomes a Clock Tower Lord and assumes broader political responsibilities. 117
Mastery of the Third Magic	186	By absorbing the Holy Grail, he masters the Third Magic, gains effectively infinite magical energy, and can freely assume forms including that of a dragon. 186

Background

Rimuru awakens in a petite humanlike body with fragmented memories and identifies himself as Rimuru Tempest. He initially recognizes the name as belonging to a slime from an anime world, while struggling with the disconnect between his prior life and the memories attached to the Tempest identity. 1 3

He is the lone survivor of the destroyed Tempest Family, a former Clock Tower Lord house. Although his lineage is regarded as a human–Phantasmal Species hybrid, Fou concludes that Rimuru's body is fundamentally that of a slime, with only traces of human blood and a human soul. 9 48 70

Appearance

Rimuru normally presents as a slight, youthful magus whose delicate features are frequently mistaken for feminine, despite his masculine identity. His human body is a maintained mimicry rather than his natural form. 1 48

• Shoulder-length light-blue hair and lively golden eyes in his usual appearance. 1
• A petite, slender build that makes driving ordinary vehicles inconvenient without altering his body. 16
• Crimson Mystic Eyes when employing his True Ancestor-derived enchantment. 175
• A white knight's uniform patterned with red flowers while acting as the White Knight. 28
• Can dissolve into liquid or reveal his slime nature to evade physical restraints. 48 157

Personality

Rimuru is calculating, politically astute, and most comfortable controlling a conflict's tempo through negotiation, psychological pressure, and advance planning. He treats force as a final option when a favorable exchange of interests is possible, but readily exploits an enemy's emotions and weaknesses once conflict begins. 34 38

He retains a personal moral compass and often protects people whose suffering does not conflict with his goals, yet his compassion does not prevent him from killing when he considers it necessary. He is notably devoted to his students and retainers, and his desire to return to his original world remains an enduring obsession. 16 19 203 219

Abilities & Skills

Slime Physiology and Mimicry

Rimuru's body is fundamentally slime-based, allowing him to maintain a human appearance while retaining exceptional resilience.

• Can liquefy his body to escape bindings such as Enkidu. 157
• Possesses super-speed regeneration and physical immunity associated with his slime constitution. 48
• Sustaining his human mimicry requires continual calculation; Fou's erasure causes the mimicry cells to collapse and rapidly drains his physical functions. 48
• Avoiding the strain by openly becoming a slime would expose his nonhuman nature to magi and worsen prejudice against him. 48

Great Sage

Great Sage functions as Rimuru's analytical and combat-support system.

• Can enter an auxiliary combat mode to take control during battle. 20
• Analyzes magecraft circuits, reinforcement markings, weapons, and opponents' abilities. 20 51
• Enabled Rimuru to analyze and replicate a magic sword during his battle with the Black Knight. 20
• Provides the calculation capacity required to maintain his unstable human mimicry. 48

Water Magecraft and Reality Marble

Water is Rimuru's signature magecraft element, used for restraint, cutting power, large-scale destruction, and battlefield control.

• Forms water prisons capable of drowning restrained targets. 69
• Compresses and sharpens water into high-pressure cutting blades. 69
• Can freeze water vapor across a wide area, immobilizing everyone in a laboratory except selected targets. 230
• His Reality Marble, Leviathan's Greeting, floods the field with catastrophic waves that engulf and eliminate the Church Executors. 26

True Ancestor Blood and Mystic Eyes

Rimuru gains additional vampire-like powers through Altrouge's blood and possesses Mystic Eyes derived from Arcueid Brunestud's vessel. 76 175

• Manifests blood-bat wings and wields the power of a True Ancestor. 76
• Mystic Eyes can bind, enchant, and alter consciousness. 175
• Their Mystery is reinforced through Age of Gods Regression, making the enchantment difficult for ordinary magi to resist through Magic Resistance. 175

Third Magic

After absorbing the Holy Grail, Rimuru masters the Third Magic. 186

• Can transform into any form at will, including a dragon. 186
• Gains infinite magical energy from the Grail's absorption. 186
• Destroys Angela, the embodiment of humanity's malice, after obtaining this power. 186

Combat Magecraft

• Uses High-Speed Divine Words, drawing Gilgamesh's attention during the Fourth Holy Grail War. 156
• Employs barriers capable of defending against Gilgamesh's Ea. 156
• Fights with magic swords, greatswords, Black Keys, and magecraft-enhanced close combat. 20 52
• Can use a clone to remain at the Clock Tower and continue teaching while personally traveling abroad. 17

Equipment / Weapons / Items

• Wuyin — A liquid familiar Rimuru can reshape into a transparent bird; he experiments on and strengthens it through absorbed materials. 10 51
• Magic sword / greatsword — A weapon he analyzes and replicates with Great Sage, later using sword-based magecraft in direct combat. 20 52
• Black Keys — Used alongside his magic blade against Burial Agency Executor Narbareck. 52
• Avalon — Saber's scabbard, which Rimuru modifies to allow Sasha to use Avalon; he later uses it to defend against Gilgamesh before reclaiming and lending it to Animusphere. 163 181 204

Relationships

• May Liddell Achelotte — His fiancée through an agreement between the Tempest and Achelotte families; a close ally who fiercely defends Rimuru's interests. 12 129
• Kuonji Alice — A childhood companion with whom Rimuru shares deep mutual understanding; she repeatedly assists his plans despite resenting being assigned errands. 12 13
• Altrouge Brunestud — The Princess of the Black and Rimuru's uneasy superior after he joins her faction; their alliance develops into mutual battlefield concern. 27 56
• Eler — Rimuru's first and most cherished disciple, whom he expects to inherit his mantle. 16
• Sasha H. Haika — Rimuru's second retainer and household steward; her family abandons the Achelotte faction to become Tempest's first factional follower. 77
• Saber — Rimuru's first retainer and summoned Servant; he entrusts her with the Tempest Family's service despite their frequent ideological clashes. 70 161
• Karna — Rimuru's Servant, whose loyalty to remain at Rimuru's side persists beyond the Holy Grail War. 157 186
• Kayneth El-Melloi Archibald — Initially a politically distant rival, later a situational ally; Kayneth attempts to cultivate ties through Reines, rescues Rimuru, and is ultimately healed by him. 14 46 161
• Aozaki Aoko — A volatile friend and frequent source of collateral damage; despite their past conflicts, she repeatedly works alongside Rimuru. 14 163
• Tohsaka Sakura — Rimuru's disciple, adopted into the Tempest-aligned Edelfelt branch and promised a branch of his Magic Crest. 126 130
• Aleister Crowley — Academy City's chairman, with whom Rimuru negotiates for scientific access and privileges while openly seeking influence above the city's existing authority. 221
• Mitsuari Ayu — A rescued recruit whom Rimuru mentors, supports in confronting Shokuhou Misaki, and appoints to lead a research facility. 222 223 230

Story Role / Major Arcs

Clock Tower Reinstatement

Rimuru learns that it is 1987, seven years before the Fourth Holy Grail War, and begins monitoring the Matou and Tohsaka families while considering how to prevent Sakura Matou's fate. He navigates the Clock Tower's Faculty Council, is reinstated as a professor, and begins rebuilding the Tempest name through teaching and political maneuvering. 4 6 12 16

The Black Princess Faction

Seeking the Dead Apostle Ancestors and the White Princess, Rimuru travels to Germany and becomes entangled with Altrouge, Sturt, and Brad. After surviving battles with the Black Knight and the Church Executors, he reveals his identity, deploys Leviathan's Greeting, and agrees to join Altrouge's faction in return for protection and help with Brad's curse. 17 20 26 27

Tempest Family Revival

Rimuru expands the Tempest Family through crest branches, loyal commoner recruits, investments, and political alliances. He becomes a Clock Tower Lord, takes control of the Department of Modern Magecraft, and develops the Tempest Group into a major mundane-world conglomerate. 86 111 117 122 127

Fourth Holy Grail War

Rimuru enters the Fuyuki conflict with Saber, Sasha, Karna, Liddell, Alice, and Aoko at his side. He confronts multiple Servants, exposes his identity as Rimuru Tempest, repeatedly intervenes in the conflicts surrounding Kayneth and Emiya Kiritsugu, and ultimately absorbs the Holy Grail to master the Third Magic. 156 157 160 163 181 186

Departure from the Type-Moon World

After dealing with Heartless and pursuing Kuro Adashino into the Fairy Domain, Rimuru prepares to leave the world in pursuit of his original home. He leaves a clone as a coordinate for a future return, entrusts the Tempest Faction's continued growth to his retainers, and eventually shatters the void after Great Sage finishes analyzing the world's barrier. 201 203 204 205

Academy City Operations

Rimuru arrives in Academy City, negotiates with Aleister for scientific privileges, and leads a dark-side organization alongside Musujime Awaki. He recruits and develops espers such as Mitsuari Ayu, targets Talent Workshop's research data, and seeks talented individuals including Shirai Kuroko and Uiharu Kazari for his institute. 221 222 229 232