Otakemaru

Otakemaru (大嶽丸) is a demon mentioned within the legend of Suzuka Gozen.

Background
Otakemaru was a demon who held as his stronghold. Suzuka Gozen sent him numerous letters proposing that they join together to take over Japan, but they were ignored due to her telling him to become her subordinate. She eventually sent a letter declaring that his "disrespect" of her made him evil, so she told him to come before her so she could kill him. She soon became involved in a separate incident with Sakanoue no Tamuramaro, initially believing him to be Otakemaru. After joining with Tamuramaro, they both later sought to slay Otakemaru, so Suzuka Gozen pretended to become his wife so she could soften his thick skin with her powers. After three years, they finally killed him.

Personality
Otakemaru completely ignored Suzuka Gozen during the time she spent as his wife, but instantly became jealous once she gave up the act and went back to Tamuramaro.

Fate/Extra CCC Fox Tail
Otakemaru is briefly mentioned in Saber's recollection of her past. He was originally going to appear in the main plot, but his involvement was ultimately scrapped. The plot would have involved the cast being trapped in a dream being created by the Moon Cell, and by capturing Saber he somehow would been able to prevent SE.RA.PH from undoing the dream.

Abilities
Otakemaru has a body as hard as stone that not even arrows can pierce. Rather than fight him in direct battle, Suzuka Gozen and Sakanoue no Tamuramaro spend three years weakening him first.