• In an alternate Tokyo, there is a secret underground district known as the Underworld; home to various black market and criminal dealings. Yuki Koyonagi, the titular 'Snow Queen' is the only daughter and heir to the infamous Koyonagi family, one of the most influential powers within the Underworld, until her father disappears suddenly and without a trace. Now in order to uncover the truth, Yuki takes over as the new head of the family and seeks 'talented' individuals to aid her in her task. What trials and dangers await the servants of the Snow Queen?