Kohaku is a male Shiba Inu Jewelpet colored cream yellow with white paws. His eyebrows are shaped like dots and colored brown. He wears a scarf pinned with an orange jewel flower.
In Jewelpet, he’s the partner of Phantom Herb Thieves member Aojisho. Kohaku is not a villain for this.
In Jewelpet Twinkle, he’s apprenticed to the Fountain Dragon. His adventures with Leon teach the latter the meaning of teamwork, for which he receives his last Jewel Stone.
In Jewelpet Kira Deco, he’s a member of Decoranain’s Shitennou. His tactic is to trick people with his cuteness and then turning them against each other.
In Jewelpet Happiness, he wishes to become as cool as Kousuke and his friends in order to impress a beautiful girl, who turns out to be Apel with his hair down. He forms a Magic Jewel with Kousuke.
In Lady Jewelpet, he’s one of the dogs used to test the Petit Ladies’ skill at dog-walking. Chosen by Luea based on the fact that he seemed more aristocratic, he gets partnered with Lillian.
He’s a minor character in the other seasons.