Sun Wukong

Sun Wukong in High School DxD is the original Monkey King from the legendary Journey to the West story, also known as the Great Sage Equaling Heaven and the Great Victorious Fighting Buddha.

He's depicted as a short (about 1 meter tall) monkey youkai with golden fur, a wrinkled face, prayer beads, and his iconic golden headband. Despite his small, elderly-looking appearance, he's an extremely powerful and ancient being — a former youkai who became a Buddha, Indra's former vanguard, and the ancestor of Bikou (the current Monkey King).

In the series, he acts as a wise, laid-back "free geezer" who follows Indra's orders when needed, joins Team DxD as a sub-leader, and provides training/advice to characters while fighting major threats like the Khaos Brigade and Hero Faction. He's renowned for his immense strength, speed, and magical abilities, often casually overpowering strong opponents.