The family of Asahina were living happily with their lives. Until a special someone in Ema's life comes into the picture and changes everything. Meet Luna, she is Ema's big adopted sister who had been living on her own since she turned 18. She's a dance teacher to kids and has decided to live with her new family. She's excited yet she has a dark past that no one knows; not even her father and Ema. Their lives changes rapidly and nothing is the same again. Find out what happens.