Ukon is Sakon's twin brother, and he's basically always riding along on Sakon's back—literally. His head sticks out while the rest of him stays merged with Sakon's body, where he's essentially dormant until it's time to fight. The two couldn't be more different personality-wise: where Sakon tends to be more calculated, Ukon's the impatient type who just wants to end things fast. He gets restless and pushy, preferring to rush through a battle rather than drag it out.
Content compiled by AnimeList.moe from publicly available sources.
