Hiromi Kirishima, nicknamed "Mad Dog," rose to prominence as a formidable delinquent at Suzuran All-Boys High School. His origins trace back to Ebizuka Middle School, where he formed the close-knit Ebizuka Trio with friends Honjō Toshiaki (Pon) and Sugihara Makoto (Mako). Renowned as Ebizuka's strongest fighters, the trio refused followers despite their fearsome reputation. Hiromi's shaved eyebrows amplified his intimidating presence, deterring even upperclassmen. Their dominance extended beyond Ebizuka, defeating rival groups from other schools. A pivotal challenge against Suzuran students led to an encounter with Genjirō Katsuragi, whose words inspired Hiromi and the entire trio to enroll at Suzuran. At Suzuran, the Ebizuka Trio swiftly conquered their freshman class by defeating every fellow newcomer. However, they soon faced opponents surpassing their previous challenges, including the legendary Rindaman, who easily defeated them. Hiromi largely avoided major first-year conflicts like the GPS vs. Serizawa's Army war and the Suzuran-Housen war, though a rebooted storyline shows the trio aiding GPS against Serizawa's Army to support senior Izaki Shun. Near year's end, Hiromi and the trio first encountered Hideto Bandō. During his sophomore year, Suzuran faced potential domination by Bandō, with Hiromi and the Ebizuka Trio standing as key obstacles alongside Rindaman. The arrival of transfer student Harumichi Bouya ignited tensions, culminating in a fierce restroom confrontation where Hiromi lost to Bouya. Despite this rivalry, Hiromi played a crucial role in forging a successful alliance between Kurosaki and Takiya students. In the war against Housen, he battled Housen leaders and officials, securing victories but ultimately falling to Tatsuya Bitō during a fight where Hiromi and Bandō faced the Bitō brothers. As a senior, Hiromi encountered freshmen Katō Hideyoshi and Kobayashi Masanara, who aimed to conquer their class before challenging him. Their plan failed, and Hiromi defeated Hideyoshi. He co-founded and led the Harumichi Family during the final battle against the Snake Heads. After graduating from Suzuran, Hiromi moved to Tokyo. There, he joined Hideto Bandō and Naraoka Tsuneyoshi to form a boy band, becoming the vocalist. During this time, he met Ishida Kotori. Later media, such as *Crows Explode*, listed Hiromi in the ninth position on the Suzuran Combat Rating. His fighting record includes victories against opponents like Akutsu and Hideyoshi, alongside losses to Bouya, Bandō (via a surprise steel pipe attack), Tatsuya Bitō, and Rindaman (alongside Pon and Mako).