OVA
Description
Ryō Takagi is a talented trumpet player performing with the jazz and blues band Moss Green and B.B. His fierce fighting spirit and uncontrollable rage in combat earn him the nickname "B.B." ("Burning Blood"), causing his eyes to turn red. He lives in Yokosuka, attends high school, and maintains relationships with his girlfriend Koyuki Matsubara and best friend Minoru "Sorry" Satou. His father, Gentarou Takagi, is a former yakuza member turned fisherman.

After saving Minoru's girlfriend Suu from a biker gang, Ryō faces Jin Moriyama in a brutal street fight and suffers his first defeat. This loss drives Ryō to abandon music, discarding his trumpet to pursue boxing. His schoolteacher Makoto Otobe, a former national boxing champion, mentors him, training Ryō to channel his "Burning Blood" rage into disciplined techniques like the "10 Centimeter Bakudan" short-range power punch. Ryō aims for a regulated rematch with Moriyama, who also returns to boxing inspired by their rivalry.

Ryō competes in tournaments, defeating opponents like Nakano "Budokan" Yasuaki. However, a confrontation with the sadistic Kijimoto Kentarou—who threatens Moriyama's sister—ends with Ryō killing Kijimoto in self-defense when attacked with scissors. This act forces Ryō into exile; he flees to the United States aboard a cargo ship. During the voyage, his mentor Wakabayashi, leader of Moss Green and B.B., dies in a storm after a crew altercation.

In San Francisco, Ryō connects with the sailor Baird and enters underground boxing on Cinderella Island, where victories promise U.S. citizenship. After a mafia conflict disrupts the arena, he is recruited into the mercenary unit "The Sleeping Lambs" by an operative known as "Magician." As a mercenary, Ryō participates in missions ranging from rescuing agriculturalist Edgar in Africa to infiltrating a Colombian drug cartel. Throughout his exile, he remains haunted by his unresolved rivalry with Moriyama and learns Koyuki is pregnant with his child.

Ryō eventually returns to professional boxing, reuniting with Moriyama for a formal rematch. This confrontation solidifies their rivalry while fostering mutual respect, as both acknowledge how their conflicts drove each other's growth. Ryō's journey spans his evolution from a directionless youth to a disciplined boxer and mercenary, culminating in his commitment to boxing as a professional career.