The trickster Horror Dantarian lures people to play his coin game but, when they lose in his fixed games, he devours their soul.
Dantalian tries this trick on Kaoru and takes her soul.
After facing off against Zero, Kouga encounters Dantarian and competes in his games to recover Kaoru's soul.
He eventually succeeds, destroying Dantarian and reuniting Kaoru's body with her soul.
Horror
Dantarian
ダンタリアン
A neon-green stag beetle Horror that possesses a con artist gambler named Kunugi Reijirou, tricking people to play a fixed coin game and after they lost, sealed their souls inside a coin.
Morinaga BAKE - Creamy Cheese, Princess song by miwa
Mintia
Trivia
Reijirou says the human soul weighs 21 grams. This is based on the experiments of MacDougall who weighed people before and after death, supposedly finding a difference of 21 grams, which he claimed was the soul leaving the body.
Apparently Zaruba detects things by their souls. Since Kaoru's body has no soul at the end, he wasn't able to tell which was the real one.