Kokuma is an Ainu, eldest son of Henke (headman of Yukput, a village now destroyed by the Wajin). Born in 1442 (year of the dog), he is a couple of years younger than the others. To his Wajin companions, his name could mean either "Little Bear" or "Space big enought for a year's supply of rice"!

Kokuma's preferred weapon is the Tetsubo, which he has mastered. Currently he is using an Oni-made Spiked Tetsubo (able to do bash or lethal Damage). He is studying the Smashing Blow okuden, but as he is coming to the conclusion that he is not not much of a student, he tends to focus his training efforts on his attributes.

Kokuma's favourite food is fish; his least favourite food is vegetables.

Kokuma married Kuchiki (daughter of a Wajin woodcutter) in 1462 (year of the horse). He rescued her when her village was attacked by oni. They have three children (as of 1468) and have also raised one bear cub.