Eris

Biodata

Power Progression

The Magic Sword Style ranks are defined by Rudeus. They measure the combination of swordsmanship and magic rather than a conventional Sword God Style title 36.

Background / History

Education at House Boreas

Eris grows up as a daughter of House Boreas in Roа. Philip hires Rudeus to teach her, with funding for Ranoa University of Magic promised after five years. She initially dismisses him because he is a child, then challenges him to a wooden-sword match. After he disarms her, restrains her with wind magic, and blocks a surprise punch, she accepts him as her tutor on a one-month trial 24 25.

Her enthusiasm for combat contrasts sharply with her resistance to academic lessons. During her first holiday, she is kidnapped after Ghislaine is lured away from the shopping street. Rudeus returns her safely to the mansion, and his promise to teach advanced techniques persuades her to cooperate more readily with her studies 26 27.

Rudeus eventually gives Eris and Ghislaine potions that grant advanced mathematical ability and knowledge of several languages, ending their academic lessons. Eris demonstrates the result by answering a division problem in Beast God Language 30.

Birthday and Acceptance of Rudeus

Preparations for Eris’s tenth birthday temporarily replace combat lessons with etiquette training. Frustrated by history and dancing, she skips class until Rudeus gives her a dance-mastery potion. She then performs flawlessly with him before Edna 37 38.

At the birthday ball, Rudeus publicly declares himself her fiancé and the incarnation of the Primordial God. Eris uses impeccable noble etiquette to extricate him from the surrounding nobles, privately scolds him for announcing an engagement without her agreement, and joins him for the final waltz 42.

Eris later helps celebrate Rudeus’s coming of age and presents the staff commissioned by Philip and Sauros. Hilda openly supports a marriage between them, while Philip offers his consent in exchange for Rudeus helping him regain leadership of House Boreas. Rudeus subsequently confesses his love to Eris, establishing their romantic relationship 50 51 52.

Demon Continent Journey

Following the Fittoa Region Teleport Incident, Eris and Rudeus travel through the Demon Continent with Rujierd, who promises to protect them until they return home. Eris initially fears him, but they become companions and register together as the F-rank party Dead End 56 65.

The journey gives Eris extensive practical combat experience. She fights black wyverns, kills two armed robbers, and trains against monsters summoned by Rudeus in the Superd Race’s former homeland 59 66 70 71.

She also duels the Immortal Demon King Atofe, whose regeneration repeatedly undoes her sword strikes. Later, Eris is found unconscious and critically weakened, with some of her red hair turning silver-white. Rudeus restores her by transferring mana through his tears 74 75 82.

Teaching, Defeat, and Return to Fittoa

In the Great Forest, Eris accepts Minitona as a pupil and promises to make her an Advanced Swordsman within seven days. The documented result is instead Intermediate Rank Magic Swordsman—still a stage Eris herself had taken half a year to reach 91 96.

Her duel with Randolph exposes weaknesses that raw power cannot overcome. His deceptive swordsmanship, Magic Absorption Stone, and hidden-eye barrier defeat her despite her enhancements and secret techniques. Afterward, she admits defeat and accepts Rudeus’s advice to observe, wait, and control her power rather than attack relentlessly 116 117 118.

Upon returning to Asura, Eris reunites with Hilda and Ghislaine in the Fittoa refugee camp. She learns that Philip is in the royal capital negotiating to clear Sauros’s name. Later, while exploring a labyrinth with Rudeus and Roxy, she counters splitting monsters with light mana but triggers a teleportation circle beneath the group 134 139.

Appearance

• Hair: Long, fiery red hair, usually loose over her shoulders, with a distinctive tuft standing up at the crown 25.
• Face: Fair skin, a small oval face, and sharp, upward-tilting eyes generally described as wine-red or crimson 25 42 96.
• Noble clothing: Initially wears an off-the-shoulder black-and-white top with a standing collar, black bow, and golden T-shaped ornament 25.
• Combat clothing: Changes into a practical swordswoman’s outfit for training; later also wears a cat-eared cloak while traveling 46 64.
• Typical posture: Frequently folds her arms, plants her hands on her hips, or stamps her feet when impatient 25 28.

Personality

Eris is proud, competitive, and quick to anger. At their first meeting, she attacks Rudeus even after conceding defeat; during lessons, she dismisses subjects that do not seem useful for sword fighting. Combat earns her attention far more readily than lectures, and she eagerly demands further training even after exhausting herself 25 26 36.

Her enthusiasm can become recklessness. She enjoys fighting summoned monsters, resists accepting defeat, and initially relies heavily on speed and overwhelming force. Randolph’s victory forces her to acknowledge the need for patience and tactical judgment 70 117 118.

Around people she loves, Eris is affectionate but easily embarrassed. She takes pride in being able to stand beside Rudeus and becomes insecure when she fears his attention is shifting elsewhere. Her attitude toward Roxy gradually changes from jealousy to explicit acceptance: she eventually urges Rudeus to confess his feelings, recognizing Roxy as a good person 95 130 137.

She also develops the ability to behave with restraint and authority. Her intervention at the birthday ball displays flawless etiquette, while her later interactions with Rudeus’s family show a maturity that surprises Paul, who had heard she was spoiled and willful 42 130.

Abilities & Skills

Magic Sword Style

Eris combines physical swordsmanship with mana enhancement and elemental sword energy under Rudeus’s instruction 28 36.

• Channels mana through her weapons to release ranged scarlet slashes 36 71.
• Alternates between heavy greatsword attacks and rapid dual-sword combinations 59 116.
• Uses enhancement magic to increase her combat performance, including Perception Boost to track minute muscular movements 74 117.
• Develops techniques incorporating dance-like steps and rhythm; Rudeus suspects her dance-mastery potion influenced this tendency 49.

Secret Techniques

• Crimson Lotus Waltz: Her first complete secret art. Uses elusive, dance-like movement and repeated attacks from changing directions; her speed and striking force increase as the sequence continues. It cracks a shield capable of withstanding a full-powered King Rank blow 49 71.
• Blood Blade Funeral Song: Produces increasingly fast attacks and afterimages. Against Randolph, it brings her blade close to his throat before his hidden-eye barrier repels her 117.
• Light Wheel Slash: A light-based sword attack used to destroy a horde of zombies in the labyrinth 139.

Touki and Sword God Style

Eris learns to circulate Touki around her blade in a controlled layer, allowing a wooden sword to survive a collision that previously shattered her weapons 46.

• Performs Sword God Style · Silent Longsword, accelerating into an extremely fast close-range strike 46.
• Has a foundation in conventional swordsmanship taught by Ghislaine, whom Rudeus identifies as her primary sword teacher 98.
• Benefits from the vest’s ongoing refinement of her Touki and physical condition 44 46.

Supporting Magic

• Voiceless healing: Heals a wound through her shoulder within a few breaths during the Randolph duel 116.
• Magic Pocket: Stores and retrieves weapons through a spatial opening; can connect her storage space with Rudeus’s for an item transfer 66 96.
• Delicious Magic: Learns to improve the taste and aroma of unpleasant roasted wyvern meat 60.
• Light mana: Coats her sword in light to defeat slimes that multiply when struck with physical attacks 139.
• Holy-light sword enhancement: Attempts to incorporate the principle of Holy Light Strike into her swordsmanship against Atofe, forming an expanding golden blade of light around her greatsword 75.

Teaching and Acquired Knowledge

• Trains Minitona to Intermediate Rank Magic Swordsman in seven days 96.
• Serves as Bunny’s opponent in a timed survival trial, then praises her use of portals and defenses 125.
• Gains advanced mathematics and several languages through Rudeus’s potions, including demonstrated use of Beast God Language 30.
• Gains ballroom-dancing knowledge and muscle memory through a mastery potion 38.

Limitations

• Mana expenditure: Prolonged ranged exchanges drain her reserves faster than Rudeus’s, forcing her to change tactics 71.
• Deception: Randolph repeatedly manipulates her expectations with false cues and unexpected attack paths 116.
• Magical counters: Her sword energy can be canceled by Randolph’s Magic Absorption Stone, while powerful barriers can interrupt even a near-successful offensive 117.
• Overexertion: After Randolph severely injures her, Rudeus must stop her from attempting another limit release 117.

Equipment / Weapons / Items

• Tyrannical Dragon King’s Frenzied Roar — A heavy greatsword given to her by Rudeus, nearly as tall as she is. Its Form Transformation splits it into two one-handed swords and recombines them as needed 58 59 75 116.
• Witness to the Sword Bearer’s Ascension to Godhood — A Quasi-Emperor Rank growth-type vest purchased by Rudeus for 1,500,000 Emotion Points. It fits beneath her clothing, applies an automatically increasing gravitational load, and strengthens her body, mana, and Touki. Quasi-God or God Rank is its stated training potential, not a rank she is shown attaining 44 46.
• Doldia protective ring — A birthday gift from Ghislaine, originally received from the Doldia chief. Protects its wearer against wolf attacks; Eris promises to wear it for life 44.
• Red-magic-stone training sword — A specially prepared longsword used during early Magic Sword Style instruction to help channel mana into the blade 29.

Relationships

• Rudeus Greyrat — Tutor, magic-sword instructor, traveling companion, and romantic partner. Eris regards him as family and takes pride in fighting beside him 25 50 52 130.
• Ghislaine Dedoldia — Bodyguard and principal swordsmanship teacher. Eris trains alongside her and deeply treasures her protective-ring gift 36 44 98.
• Philip Boreas Greyrat — Father. Arranges her education and makes his approval of her marriage to Rudeus conditional on political assistance 24 51.
• Hilda — Mother. Chooses Eris’s clothes, supports her relationship with Rudeus, and reunites with her in the refugee camp 30 50 134.
• Sauros — Grandfather. Mobilizes the household’s forces after her kidnapping; Eris later worries about the accusations against him 26 134.
• Rujierd — Protector, fellow Dead End member, and training companion. She initially fears him, but he later guards her while she is critically weakened 56 65 71 82.
• Roxy — Traveling companion whom Eris initially views with jealousy. She later encourages Rudeus to pursue his feelings for Roxy 95 137.
• Minitona — Swordsmanship pupil. Reaches Intermediate Rank Magic Swordsman under Eris’s seven-day instruction 91 96.
• Aisha Greyrat — Rudeus’s younger sister. Eris immediately warms to her and asks to be called “big sister” rather than “sister-in-law” 127.
• Randolph — Opponent whose victory teaches Eris the limitations of speed, strength, and relentless aggression 116 117 118.

Ambition

Eris resolves to become a magic swordswoman stronger than Saint Millis and produce a sword-energy strike wider and longer than the Holy Sword Highway 88.