Rui is the youngest member of the Kizuki and the holder of Lower Rank 5, his blood demon art is based off spider cobwebs and strings, which can make threads that can cut through anything, and they can trap and injure people badly and he can make anything out of them. Rui has a demon family which he made of composing random weak demons. He is the second weakest Lowermoon and Kizuki Member. Rui's blood can turn people into versions of himself to be part of his family if Rui wishes so.