Kouga is a wolf demon who you don't see until very late in the show. His wolf pack does as he says, and it was Kouga who let the wolves destroy and eat everyone in Rin's village. He possessed 3 jewel shard when meeting Inu-Yasha and the crew, and then kidnaps Kagome. He explains to her that monsters attack and kill members of his wolf clan, and they possess jewel shards. He needed Kagome to help destroy the monsters because she could detect the jewel shards. He ends up falling in love with her, and was bold enough to tell her! I don't think Inu-Yasha was so pleased though...
