Mayumi Tetsuji is a fictional character from Crows x Worst, part of the delinquent manga and anime universe centered on Suzuran and surrounding schools. She is portrayed as a supporting character associated with the series’ cast of tough, streetwise youths. Her role is to help flesh out the social world and rival dynamics around the main fighters, contributing to the series’ themes of loyalty, reputation, and school gang conflict. She is not one of the central protagonists, but appears as part of the broader ensemble.