Beam is a Shark Fiend and a Public Safety Devil Hunter from Tokyo Special Division 4. He is devoted to Chainsaw Man, always referring to him as "Lord Chainsaw" or "Master Chainsaw". Beam is very innocent and almost childlike, often getting excited about rain and water. He has the appearance of a muscular teenage boy around the age of 17, with only the top half of his head resembling that of a shark. With no visible eyes, the upper half of Beam's head resembles a shark head.