Calla has been an orphan since childhood and was adopted by the werewolf Rogue "Nico". On a full moon night, she got lost in the forest and accidentally encountered Kael, the Wolf King, during his estrus cycle. He recognized her as his destined mate, leaving behind a token and a promise symbolizing her as the Future Luna.
However, fate played a cruel trick. Nico fell seriously ill, requiring a huge sum for surgery. Left with no other options, Calla had to turn to Kael for help. Yet, because Nico's family was once exiled for betraying the Blood Moon Pack, Calla dared not reveal the true reason for needing the money.
Kael, misunderstanding her intentions, thought she was a gold-digger. To humiliate her, he forced her to sign a three-year kept woman contract. Throughout those three years, love and misunderstanding entangled them in a painful struggle.
As the contract nears its end, Calla learns that Kael is set to marry the daughter of another Wolf King for an alliance. Choosing to leave, she unexpectedly discovers she is pregnant. Torn between her choices, where will she go? And when will Kael finally learn the truth behind Calla's sacrifices...
