Koukin has demonstrated some great power when he defended Hakufu and Kakouton from the Ugan gang, which astonished even Kakouton. He stayed behind to fight and eventually was captured, allowing the other two to escape. While being held captive in Kyosho, he was seduced by three beautiful girls (one of them being Seito's spy, Shokan, who reveals her identity to him afterwards) in an attempt to make Koukin betray Nanyo and fight for Sousou. This is, in fact, part of the plan for the Battle of Sekiheki; with Koukin personally enacting "the plan of bodily harm." Once the Kyosho forces are scattered in the battle he breaks free, easily defeating Kaku and Gakushin. He is currently trying to locate the separated Nanyo and Seito forces in order to take command, as per his fate in the battle.
In the anime, he is the only character whose after-episode biography in the first season poked fun at him, saying that after he got lost in a forest, Hakufu nicknamed him "The Lost Koukin", and as a child, he was called "Crybaby Koukin" by other children because he always cried when others bullied him, and Hakufu was usually there to protect him from bullies. Koukin was unable to stop Hakufu's dragon when she fought Ukitsu; instead he got pummeled to near death in the attempt only to have Hakufu stop her dragon on her own. In Dragon Destiny, after hearing of Hakufu's supposed demise, he blames Koumei for manipulating the events that led to Hakufu's fight with Sousou. However, Kanu proved to him that it was Hakufu's choice to challenge Sousou, and her fight with Kanu was one out of respect as fighters and not out of hatred. This leads to Nanyo and Seito forming an alliance to face Kyosho. He returns to being a student after the Battle of Red Cliffs.
|Ikkitousen: Xtreme Xecutor||Season 4||TV||12||0||0|
|Ikkitousen: Great Guardians OVA||Specials||OVA||6||0||0|
|Ikkitousen: Great Guardians||Season 3||TV||12||0||0|
|Ikkitousen: Dragon Destiny OVA||Specials||OVA||6||0||0|
|Ikkitousen: Dragon Destiny||Season 2||TV||12||0||0|
|Ikkitousen DVD Specials||Special||3||0||0|