Juouheika To Sunakaburi No Hanayome summary:

Just as Sunakaburi was almost killed by slave traders, he was saved by a snow leopard, the Beast King. Sunakaburi, who did not belong because of his different fur color, was told by the king that he was his “destined mate”, and was given beautiful clothes, a soft bed to sleep in, and delicious food to eat instead of leftovers. The king even gave Sunakaburi a lovely name, “Kouran”. Overjoyed, Kouran wants to be of use to the king, but Kouran doesn’t really know what a “destined mate” is…