Mei

Biodata

Feature	Details
Name	Mei (芽衣); also known as Raiden Mei
Alias(es)	Dr. Mei; Herrscher of Thunder; Origin Herrscher
Gender	Female
Affiliation	Senba Academy; Flame Chasers; World Serpent; Schicksal
Occupation/Role	Researcher; scientist; Valkyrie; captain of Schicksal's Third Squad
Status	Active
First Appearance	Chapter 3

Power Progression

Stage / Realm / Level	Chapter	Notes
Researcher / Dr. Mei	14	Joins the Flame Chasers as a researcher and studies under Mobius; later develops the Mete-Morph hypervariable-factor synthesis reagent for creating Fusion Warriors.
Herrscher of Thunder manifestation	97 99	Awakens lightning-based Herrscher power while protecting Kiana; a restraint program is initiated.
Herrscher power burst	232	Fights alongside Raven while seeking Kiana, but her surge of power is not yet a qualitative transformation.
True Herrscher of Thunder	249 250	Accepts and merges with her Herrscher/Stigma consciousness after Benares sacrifices itself; defeats Nihility and gains full control of her Authority.
Fully mastered Herrscher Authority	305 312 319	Resists the Herrscher of Domination's attempt to seize her Authority; defeats its puppets in a direct contest of strength.
Heir to the Flame-Chasers' Sigils	335 434	Receives Sigils from the Flame-Chasers and later gathers their powers in the Elysian Realm.
Origin Herrscher	489 490	Passes trials of resolve, courage, and conviction; inherits Origin with Elysia's guidance and the Flame-Chasers' blessings.

Background / History

Mei attended Senba Academy in eastern Changkong City. Her father was a world-renowned electromagnetic physicist, and his influence led her to focus almost entirely on study from childhood. Her constant reading earned her a reputation as the academy's bookworm. 3

At Senba, she met transfer student Kevin. Although Kevin persistently tried to court her after falling in love at first sight, Mei initially ignored him in favor of her studies. Over time, she became accustomed to his presence. 3

Mei and Kevin later joined the Flame Chasers, where they were assigned to separate departments: Kevin as a soldier and Mei as a researcher under Mobius. Mei became known as Dr. Mei and created Mete-Morph, a reagent that enabled suitable candidates to become Fusion Warriors under extreme conditions. 14 69

Appearance

Mei’s appearance changes substantially with her Herrscher transformations.

• Uses a katana as her standard weapon. 223
• Her Herrscher of Thunder form manifests purple lightning and a regal, queen-like presence. 97 250
• She possesses horns, which become a recurring point of attention in the Elysian Realm. 371 378
• As the Origin Herrscher, she wears a primarily white outfit with colorful accents, a divine wheel behind her, and noble weapons arranged at her sides like wings. 490

Personality

As a student, Mei was reserved, studious, and intensely focused on becoming a scientist. Her early single-mindedness made her dismissive of Kevin’s attempts to get close to her, though she gradually accepted his companionship. 3

Mei is defined by fierce devotion to those she loves, particularly Kiana. Her inability to protect Kiana repeatedly causes guilt, hesitation, and desperation; ultimately, she accepts the Herrscher of Thunder’s power and joins World Serpent to keep Kiana from further endangering herself. 232 247 250

Her later experiences make her more analytical, assertive, and willing to challenge manipulation directly. She sees through the Herrscher of Erosion’s deception, investigates the Elysian Realm’s mysteries, and rejects Aponia’s belief in an unchangeable fate. 375 409

After inheriting the Flame-Chasers’ legacy, Mei becomes more accepting of Kiana’s agency. Rather than stopping Kiana from making sacrifices unilaterally, she resolves to stand beside her through the outcome. 462 486

Abilities & Skills

Scientific Research

Mei is an accomplished researcher who becomes known as Dr. Mei within the Flame Chasers.

• Developed Mete-Morph, a hypervariable-factor synthesis reagent used to rapidly produce Fusion Warriors. 69
• Studied under Mobius after joining the Flame Chasers. 14
• Demonstrates strong analytical ability, particularly when uncovering the Herrscher of Erosion’s motives and weaknesses. 409
• In a World Bubble, Dr. Mei devises a long-term plan to preserve its people by obtaining time through a deal with World Serpent. 460

Herrscher of Thunder Authority

Mei wields lightning-based Herrscher power and eventually fully merges with her Stigma consciousness.

• Annihilates a Temple-class Honkai Beast with a lightning beam during an early manifestation. 97
• Can transform into lightning during aerial combat. 252
• Gains full Herrscher power after accepting her inner Herrscher consciousness. 249 250
• Her fully mastered Authority cannot be stolen by the Herrscher of Domination. 312
• Uses crimson lightning to destroy Honkai Beasts and overpower Domination puppets. 319 391

Swordsmanship

Mei is a longtime katana user and an experienced combatant.

• Uses her katana as her regular weapon. 223
• Battles Kiana while deliberately controlling her strength to avoid seriously harming her. 251
• Cuts through a shared memory scene rather than injuring Kiana within it. 251
• Fights numerous powerful opponents, including Nihility, Raven, Chrono, Mobius, Aponia, and the Herrscher of Erosion. 232 249 339 374 409

Origin Authority

Mei inherits the Authority of Origin after completing trials tied to her past, responsibility, and the future of humanity.

• Is tested on whether she can bear Kevin’s will, place the Crown of Finality on Kiana, and ensure the world’s continuation. 487 488
• Becomes the new Origin Herrscher with Elysia’s guidance. 489 490
• Carries forward the Flame-Chasers’ stories and will. 489
• Acts as the first connection candidate when Kiana serves as a medium for the group. 502

Equipment / Weapons / Items

• Katana — Mei’s standard weapon. 223
• Mete-Morph — Hypervariable-factor synthesis reagent developed by Mei for Fusion Warrior creation. 69
• Flame-Chaser Sigils — Inherited from the Elysian Realm’s Flame-Chasers. 335 434
• Vill-V’s beacon/compass — Used while navigating the Stigma Project’s network and escaping dream-like spaces. 484 485

Relationships

• Kiana — Mei’s most important person. Mei repeatedly risks herself to save Kiana, leaves her to join World Serpent for her protection, and later resolves to stand beside her rather than decide her future for her. Their feelings become mutual and explicit. 232 252 466 486
• Kevin — Mei’s childhood companion and fellow Flame Chaser. In the Previous Civilization, they are romantically devoted to one another; Mei entrusts him with the Chimera Project and later the Stigma Project. 3 38 468
• Herrscher of Thunder — Mei’s Stigma consciousness. Initially divided from Mei, she later merges with her; they eventually reconcile after confronting their differing views of Kiana. 249 486 487
• Benares / Bella — Benares protects Mei from a fatal attack and sacrifices itself, leaving its body for Mei to control. 249 250
• Raven — World Serpent comrade and investigative partner. Raven allows Mei to pass after recognizing her determination, and the two later confide in each other about their losses. 232 304
• Elysia — Guide, mentor, and close companion in the Elysian Realm. Elysia helps Mei inherit Origin, while Mei comes to deeply understand and preserve Elysia’s legacy. 335 435 489 490
• Mobius — Mei’s former mentor in the Flame Chasers and later an adversary in the Elysian Realm. Mei defeats Mobius after refusing her attempted possession. 14 338 339
• Bronya — A close teammate. Bronya rescues Mei after a Herrscher battle, later helps her recognize that she and Kiana are close to reconciliation. 100 462
• Dr. Mei — A counterpart from a World Bubble. Mei questions but ultimately trusts her plan to reconnect the World Bubble to the Imaginary Tree. 460 461

Story Role / Major Arcs

Flame Chasers Era

Mei begins as a gifted student aspiring to science, then joins the Flame Chasers as a researcher. She becomes Dr. Mei, studies under Mobius, develops Mete-Morph, and supports projects involving Fusion Warriors and humanity’s survival. 3 14 69

Herrscher Awakening and Kiana’s Rescue

As Raiden Mei, she manifests the power of the Third Herrscher/Herrscher of Thunder while defending Kiana. Her Herrscher identity is initially divided between Mei herself and a separate Stigma consciousness. 97 100 123

World Serpent and Thunderous Sanction

Unable to protect Kiana through conventional means, Mei agrees to join World Serpent after Kevin offers a path to save her. Following Benares’ sacrifice, she accepts her Herrscher nature and becomes the true Herrscher of Thunder. She defeats Kiana to stop her from destroying herself, then leaves Senba Academy to bear the burden alone. 247 249 250 252

Herrscher of Domination Investigation

Mei works with Raven to investigate the Thousand-Man Herrscher. In the Domination Theater, she refuses attempts to tempt her with an ordinary life with Kiana and proves that her fully mastered Authority cannot be stolen. 304 305 312 319

Elysian Realm

Mei enters the Land of the Past to learn the truth of the Previous Civilization and the Flame-Chasers. She gathers Sigils, defeats Mobius, resists Aponia’s prophecy, investigates the Realm’s collapse, and confronts the Herrscher of Erosion. 335 339 375 409

Through Elysia’s memories and the Flame-Chasers’ final farewells, Mei comes to understand their sacrifices and accepts responsibility for carrying their legacy forward. 423 435 437

Reconciliation and Origin

Mei reunites with Kiana and Bronya, reassessing her earlier decision to leave Kiana behind. She and Kiana acknowledge their feelings and agree they no longer need to force one another to change. 462 466

After overcoming trials of resolve and confronting her past self and Herrscher consciousness, Mei inherits the Authority of Origin. She becomes the new Origin Herrscher, blessed by the Thirteen Flame-Chasers and entrusted with their legacy. 486 489 490

Notable Quotes

“You are the most important person in my life.” 252

“If saving you is a sin, then let me be the sinner...” 252

“It's simple – you're too weak.” 319

“No one has ever been more sincere than her, and no one has ever been purer than her...” 423

“And I will continue to pass down your deeds and will, so that generation after generation will know that there was once a group of people who lived brilliantly and dazzlingly.” 489

Trivia

• Mei was widely known as a bookworm at Senba Academy. 3
• Players and viewers frequently called her “Housewife,” a nickname that became increasingly contested after her return as the Herrscher of Thunder. 123 211 251
• Elysia publicly spread the story of touching Mei’s horns throughout the Elysian Realm. 371
• Mei is described as a perennial katana user. 223