Two heroines, abandonment, fetters, growth. Sai is a "sister", an orphan who was raised by a wild cat when she was a child, and was taken away to become the first "cat" of the manor. Seringa is the "sister", the daughter of a wealthy businessman, who was sold by her parents to the manor to pay off her debts and became the second "cat", Sai is constantly searching for freedom, expecting to live with the real "like", and facing the fleeing Sai, Seringa grabs her by the throat - "You and I are the same, you should be with me."