Raizen is a powerful demon king in Yu Yu Hakusho and one of the three rulers of the Demon World. He is the ancestor of Yusuke Urameshi and a legendary figure known for his immense strength and pride. After falling in love with a human woman, he chose to stop eating humans, which weakened him over time but highlighted his honor and conviction. Raizen plays a crucial role in the Demon World saga as a catalyst for the balance of power and Yusuke’s heritage.