I am "kept" by the mad love of these twins. What is the sweet ending to this twisted form of love...?

When Hokuto Yonaga turned five, her father took her to the Fudou Zaibatsu mansion. There they met the heirs to the Fudou family, the beautiful identical twins Tsuzuri and Katari. For thirteen years since her father sold her to them as a plaything, Yonaga has been at the mercy of the whimsical and sadistic twins, who are the complete opposite of their beautiful appearance. She secretly harboured feelings of hatred towards the twins who had ruined her life.

However, when the three of them start living together on the occasion of entering university, the relationship between Tsuzuri and Katari over Yonaga gradually begins to unravel.
Then one day, a man called Yagami appears in front of Yonaga...

A forbidden love-hate story full of beautiful madness begins here.