Gridman is the titular hero of the anime series SSSS.Gridman. He is a mysterious Hyper Agent from another dimension who merges with the protagonist, Yuta Hibiki, to fight against kaiju monsters threatening the city. Gridman serves as a mentor and protector, guiding Yuta and his friends as they uncover the truth behind the strange events in their world. His presence is crucial in battling evil and helping the characters grow throughout the series.