It is the Meiji era. Satoko, who is said to have little time left to live, was kidnapped and brought to the ‘island of prostitutes’.

To get Shinpei the assassin on her side, she makes a bold proposal to marry him! But with Shinpei’s abnormal approach to love, she finds herself trapped in an even more precarious situation…

The two hatch a plan for Satoko to disguise herself as a prostitute to flee the island, but Shinpei refuses to let any man lay a finger on her: I will be the one to protect you...

While Shinpei's affection is slowly swaying Satoko’s feelings for the man, her guilt about their fake engagement begins to surface as Shinpei starts to pick up on her behaviour…