Dei Surugi is a student from class 1-A in the anime Dead Account, known for his role as a primary rival and antagonist to the protagonist, Soji. He is characterized as a psychopathic individual who displays a cruel and provocative nature, often engaging in instigative behavior to goad his opponents. Physically, Dei is a teenage boy with distinctive red eyes and short red hair that falls to his ears. His appearance is further defined by his fashion sense, which includes tinted glasses, earrings, boots, nail polish, and a belt.

In the story, Dei serves as a formidable obstacle for the protagonist class 1-B, representing the individualism of class 1-A in contrast to the team-oriented spirit of Soji's class. His personal history with Soji is deeply antagonistic and rooted in tragedy, as he is the one who willfully burned the hair barrette belonging to Soji's younger sister, Akari, reducing it to ashes. This act establishes a profound and bitter personal conflict between the two characters.

Dei is noted to be a flamebaiter, and there are implications that his fire-based abilities may not be cybernetic in nature, setting him apart from other characters who rely on technological enhancements for their powers. His role in the narrative often involves orchestrated confrontations, such as a planned brawl between his class and Soji's class, where he and his group engage in psychological warfare and smack talk before showcasing their combat capabilities. Throughout the story, Dei Surugi remains a key figure of opposition, driving conflict through his cruel personal history with the protagonist and his volatile, provocative personality.