It's a shame it has no gender

–Benimaru, on Rimuru's transformation

"Flame Lord" Benimaru "赫怒王"(フレアロード) 紅丸(ベニマル), "Kakudo Ou"(F u r e a R o o d o) Benimaru, lit. "Scarlet boy"」 is a Flame Spirit Oni and a loyal follower of Rimuru Tempest, the King of Tempest.

He is the Commander-in-Chief of Tempest, one of Rimuru's Twelve Patrons and also one of his three strongest subordinates, including Diablo and Zegion.


Benimaru has hair burning like a crimson flame. Two jet-black horns protrude from below the hair. Glowing more brilliantly than obsidian. Although he used to be big and bulky, his height decreased to 180 cm, and his body tightened.

Benimaru received a kimono that turned blood red to match his aura.


Benimaru has a carefree personality, that of an excited and confident man. Even so, he is actually really cautious and cunning as well.

Benimaru felt hesitant when faced the responsibility to take over the position of the Ogre Tribe village chief. Thus, he is content with his current position with Rimuru as the Lord he serves. As the military commander, he merely wishes to rampage to his heart’s content. Had he become chief, he could not ride off to battle, but now it was different. He can participate without any concern.


As the young master of the ogre village, Benimaru would have taken up the weight and responsibility of a leader had ten thousand Orcs not invaded his town and slaughtered all but six ogres. 

Escaping the disaster, he runs into Rimuru. With the turn of fate, he pledges his loyalty to Rimuru after witnessing his lord’s benevolence and a promise of retribution. 


Forest Disturbance Arc


Benimaru was introduced in the Forest Disturbance Arc as the Young Master of the Ogre Tribe. They were attacked by a horde of Orcs, who had a Devil wearing a mask accompanying them, acting as their leader. In the Web Novel, this masked devil was Gelmudo whereas, in the Manga, it was Footman.

Having his entire tribe eradicated, Benimaru and his 5 remaining tribe members flee with great regret, only to encounter masked devil who was leaking great amounts of power. Afraid, angry and frustrated at his failure to flee, Benimaru called out to this masked monster and prepared to attack.

Meeting with Rimuru

This person was actually Rimuru, who had just exited the Cave of the Seal after testing out his newly acquired powers from Shizue Izawa and Ifrit. Since he was wearing Shizu's anti-demon mask, he had mistaken him to be the same devil, if not an accomplice.

In the Web Novel, it isn't clearly explained how Rimuru convinced them that he was not the one who attacked their tribe, but simply that he did. In the Manga, he ended up fighting them until they were shown the utterly devastating difference between him and their powers. Preparing to sacrifice their lives on the line so that their Young Master and his little sister, the Young Mistress, could escape, the 4 once again stood in front of Rimuru, only to be stopped by Benimaru's yet unnamed younger sister, Shuna, who explained that Rimuru was probably telling the truth and that he has no connection to the ones who attacked. With the situation having finally calming down, Rimuru used healing potions on them and his injured subordinates and returned back to the village with all of them.

After some rest, Rimuru learnt about his circumstances and asked him if they were willing to become his subordinates, even if it's temporarily. Since they too would need to fight these orcs, it would be better to join forces, was what Rimuru had said. In the Web Novel, he easily accepted after some thought. In the Manga, he asked for some time to think about it and walked away, only to meet his childhood friend and rival stating that it wasn't a bad idea after looking at the state of the goblin village Rimuru ruled over. After some frustrating reminiscence, Benimaru finally decided to accept and finally, as a symbol of Rimuru's rulership, granted the six of them names: Benimaru, Shuna, Souei, Shion, Hakurou and Kurobee, and thus they all evolved from Ogres into Kijin.

Against the Orcs

Some days passed and Benimaru, Hakurou, and Souei trained together to get used to their new found powers.

Life in the Royal Capital Arc

Birth of a Demon Lord Arc

Saint Demon Confrontation Arc

Founding the Demon Capital Arc

Demon Lords' Gambit Arc

Empire's Invasion Arc

Ryuma Clash Arc


Major and Minor Battles


Ch. Evolution Stage Trigger for


Rank EP New Skills / Abilities


Ogre B+
27 Oni Named by Rimuru A-
31 Battle Black Lightning



Magical Clothing

37 Battle Hell Flame (Black Flame Prison)

Shapeshifter (weakened)

Extra Area Boundary

Fire Manipulation

72 Eating Shion's


Resistance Poison Resistance
74 Fair Oni Rimuru's Evolution

To True Demon Lord

A 213,000 Unique Generalissimo
Battle Demon Flame Transformation (Fire Transformation)
Extra Multiple Barriers

Spatial Travel

Daily Magic Perception

Heat Detection


Herculean Strength

Resistance Physical Attack Nullification

Pain Nullification

Status Change Nullification

Spirit Attack Resistance

Holy Magic Attack Resistance

Natural Effects Resistance

106 Weapon Katana: Crimson Lotus Edge
114 Battle Rebirth Flame (Intermittent Blast of the Hazy Black Flame)
Extra SwordSkill: Dim Current Slash
17 Flame Spirit Oni Forceful evolution into a Demon Lord by Rimuru SS 1.000.000+ Ultimate Thought Acceleration

Unifying Control

Heat and Light manipulation

Space Manipulation

Multi-layered Barrier


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