Mordred

Mordred was the 9th seat of the Order of Diabolos and a knight in the round table. However, he was killed by Shadow and the Shadow Garden.

Personality
Mordred is a delusional-yet-foolish psychopath. According to Shadow, he is nothing more than a mook and even the only reason he absorb Ragnarok was its stupidity, making Mordred as a complete idiot.

Return to Earth
Following his death, Mordred's severed head was transported to Earth alongside the Shadow and Beta. There, it was found by Akira Nishino. He later attempted to use it in his magic experiments by injecting 'Natsume' with his blood but was assassinated by Yuka before he could do so. Yuka would go on to instead inject Akane, causing her to go berserk until she was stopped by the Shadow. It is unknown what became of Mordred's head afterward, whether Beta took it back with her or she left it behind.

Powers & Abilities
He was a skilled swordsman with the use of an legendary magic sword. however, he was stood no chance against the forces of the Shadow Garden forcing him to summon Ragnarok. Despite his desperate actions, he was still not able to best Shadow.

In the web novel, he was able to heavily injure Epsilon in one-to-one combat; although he caught her off-guard.

Trivia

 * Mordred is based on the knight Mordred from Arthurian legend.