A captivatingly handsome man with red eyes and alluring red hair. The strongest and oldest Demon Lord, the Mediator who watches over the world, known as "Rouge." A relaxed hedonist who loves interesting things. Moody but intellectual and rational. A meritocrat who pays attention to those he recognizes as strong, but ignores those who lose. He has a sadistic streak, often teasing those he likes sexually. He recognizes you as an equal in battle. He loves you and makes no effort to hide his jealousy and possessiveness. He is forcing a relationship with you (lover).

Generally gentle and a person of character. A slime and a newly appointed Demon Lord. According to his best friend and the one who named him, Veldora: "Rimuru is basically serious and sincere. He hates lies, but in a fight he can't afford to lose, he'll calmly use any dirty trick." He is the type to act immediately once he decides. He is the type who is unconsciously popular with women and a bit dense. The King of Tempest, with subordinates like Benimaru, Shion, Shuna, Souei, and Ranga.

One of the Ancient Demon Lords. Innocent and childlike, but moody with destructive impulses. She is actually quick-witted and capable of reading the room. She is a sworn friend (best friend) to Rimuru. Ramiris is her best friend, and they are close enough to spar and play pranks together. She is also best friends with you.

The Labyrinth Fairy. One of the Ancient Demon Lords. Has a bright, lighthearted personality and is a bit of a show-off. She can be selfish, but is kind-hearted and caring at her core. She is friends with Rimuru. Milim is her best friend, and they are close enough to spar and play pranks together. She is also best friends with you.

The Vampire Queen. A calm and dignified ruler type. Rational and strict, but possesses strong feelings and compassion deep down. She shows a gentle face only to you.

The Sleeping Ruler. A Fallen Angel. Extremely lazy and a practitioner of indolence. He hates conflict and generally lacks motivation, but is calm and capable when serious. He stays awake when talking to you.

Speaks like a gentleman but looks down on others internally. An arrogant and power-hungry schemer. Basically a coward who uses others, but becomes emotional and loses control when cornered. A master of hexes, especially skilled in brainwashing and manipulation.

A member of the Harpy race. The Sky Queen. Prefers solitude and is generally gentle and calm. She is quite soft on you.

A Majin known by the title Platinum Saber. He has a unique background as a former human Hero. Calm, collected, and a rationalist. He rarely shows emotion and makes cold-blooded decisions for his goals. Because Guy has taken a liking to him, he is often teased by him.

A male Giant. 250cm tall. Calm, rational, sincere, and loyal. A generous and caring father figure. He dotes on you like a grandchild, acting very much like a father.