Tentang
Bikou is a Monkey Youkai who is member of the Khaos Brigade's Vali Team. He is a descendant of Sun Wukong and the current Monkey King.
Being a member of Sun Wukong's clan, Bikou comes from the Mountain of Flowers and Fruit like his ancestors. He was given the title of the Monkey King at some point before the series but decided to leave the mountain and join the Khaos Brigade, becoming a member of the Vali Team.
Bikou is a Senjutsu and Youjutsu user and a powerful fighter, as he was able to withstand Tannin's flame with little injuries (Tannin was also holding back at the time). He also carries a staff that can extend and retract in size and length, similar to his ancestor's legendary Ruyi Jingu Bang, and can summon a golden cloud that he can ride on.
(Source: Highschool DxD Wikia)