Sonic Speed Monkey is a fictional character from the anime series 'Kekkai Sensen' (Blood Blockade Battlefront). Sonic is a small, hyperactive monkey with extraordinary speed, often serving as a companion to Zapp Renfro, one of the protagonists in the series. Despite his diminutive size, Sonic plays a significant role, often being used for reconnaissance missions or as a distraction during battles. His agile and mischievous nature endears him to the team, providing both comic relief and unexpected assistance in their various adventures within the chaotic and supernatural city of Hellsalem’s Lot.