Serizawa Tamao aka King of Beasts was the leader of the "Serizawa Army" and formerly the strongest senior student at Suzuran All Boys High. Feared as a beast in a brawl the only thing that concerned him was the sophomore Rindaman, the legendary man that no one could beat. That is until Genji Takiya transferred to Suzuran, and then a war between the two began.
His strength is known by delinquents and Yakuza alike, and well respected by Housen's head Narumi Taiga. He's defeated the Mikami Brothers, Izaki Shun and has defeated Takashi Makise numerous times. He was on track to completely conquer Suzuran but was defeated by Genji during the final confrontation between their factions.
A very humble man, Serizawa doesn't take kindly to people who look down on the poor stating that those who know poverty are strong. His partner in crime is Tokio Tatsukawa and they have been causing trouble at Suzuran together since they were first years.
He later gathered his faction and followed the GPS during their assault on Housen Academy. Serizawa himself acknowledged Genji Takiya as their Captian.
He defeated Housen's Ryō Urushibara in a one one one to avenge Shoji Tsutsumoto.
In his first year at Suzuran, Serizawa became a notable figure. Being one of the strongest freshmans and feared by his seniors, he was labelled as the King of Beasts. He became friends with Tokio Tatsukawa and wreaked havoc around Suzuran. Tokio is his closest friend. He became apart of Kawaishi Noboru's faction in the battle between Suzuran and Housen, which resulted in the death of Housen's leader, Makio Bitou and the creation of the non aggression pact.
In his second year, Serizawa formed his own faction, Serizawa Army. Serizawa had incorporated into his faction, Shoji Tsutsumoto, a former Judo champion, Yuji Tokaji, fought Serizawa for two years and could never beat him. Tokaji is the brain of Serizawa's Army. Serizawa has fought fellow second year Takashi Makise on many occasions and has always beaten him. However, Takashi Makise continues to fight Serizawa and refuses to join him. At the end of his second year at Suzuran, Genjirou Katsuragi, the top man at Suzuran, graduates, making Serizawa and his faction the top of Suzuran.
In his final year at Suzuran, Serizawa is favoured as being the one to conquer Suzuran, a feat never before achieved in the history of the school (until seven years later by Hana Tsukishima). At the begining of the third year, Genji Takiya arrives at the school and graffitis his name over Serizawa's graffiti Serizawa, King of Suzuran. After a comical situation when Genji prevents Serizawa from winning money in a game of Octopus(Scramble), Serizawa and Genji are about to fight. Before they fight, the Mikami brothers interupt, wanting to fight Serizawa. Serizawa defeats the Mikami brothers with ease and they follow Serizawa, joining his army. With Genji forming the GPS, Genji challenges Serizawa for the top spot. Serizawa's Army and GPS begin one of the biggest battles within Suzuran. With Serizawa's army nearly finish off GPS, The Front of Armament led by Bando arrives siding with GPS, changing the balance of the battle. Only Serizawa and Genji remain standing and begin fighting. The fight went back and forth, lasting til sunset. Genji came out victor.
After the fight with GPS, Serizawa refuses to join GPS as him and his followers believe that had not The Front of Armament arrived, Serizawa would have won. With the non aggression pact being broken due to Genji unintentionally protecting Kawaishi Noboru by striking a Housen student, calls for an alliance between Serizawa's Army and GPS are brought up. After Suzuran is set on fire, Genji challenges Housen and organises the fight to be held at Housen. However, Genji decides to go by himself without his faction. Due to his action, Serizawa and his faction join GPS, with Serizawa saying to Narumi Taiga Did you really think we wouldn't follow our captain? aknowledging Genji as the leader. Suzuran fight their way into Housen. Before reaching the roof top to confront Narumi Taiga, Urushibara Ryo is guarding the door, only allowing Genji through. When Serizawa asks him if he was the one who hospitalised Shoji Tsutsumoto, he tells Genji to handle Taiga while he deals with Ryo. Serizawa defeats Ryo and joins Genji on the roof top. After Genji defeats Taiga and Suzuran's victory over Housen, the team return back to Suzuran. On Serizawa's final day of school before graduating, Serizawa places a bet on Ganji beating Rindaman in a final fight. However, Genji would lose yet again.