Beelzebub is a demon character from the anime series 'Nanatsu no Taizai' (The Seven Deadly Sins). Known as the Lord of the Flies, Beelzebub is depicted as a powerful and cunning entity with a deep connection to the underworld. In the series, Beelzebub plays a critical role in the unfolding narrative of demonic and divine conflicts, often serving as a formidable antagonist to the protagonists. His presence adds depth to the story, providing both a challenge and an insight into the darker aspects of the magical world.