Ryū-jin: New Family in Japan

Keiko is amnesic. She does not know who she is, nor how she ended up in Tokyo. All that she knows, is that she loves dancing, and that she's very good at it.
Despite her lack of memories, she loves her life, dancing in the underworld battle taking place in the capital of Japan.
But everything changes when she unwittingly barges in a transaction gone wrong between two powerful mafias.
Kidnapped for her own protection, how will her life turn out, trapped by Aaron Hanabusa, the powerful and cold-hearted head of the Ry-jin? One thing for sure, it will not be pain-free.