Hiko Saruta

Harsh, cruel, brutal, extremely powerful and skillful as a warrior. Real butcher. He killed every single person in country of Hi (Fire) followed by order from Himiko-sama. But after he met Nagi something changed him. In past his clan was annihilated, he is only survivor. Has been taken to Yama Tai Koku.

His name consist of three kanji: 猿 monkey (saru) 田 rice field (ta) and 彦 boy (hiko - actually very old one). Maybe it's mean nothing but it can help understand in some way his personality.