Simone yousuke and yukii yousuke are identical twins who were separated when a hijack came when boarding to aramasu island. Yukii unluckily kidnapped by the terrorists, while simone luckily stayed with their family. 13 years later, things become bizarre, simone found yukii is still alive and finds her. Upon getting her back is the means of losing simone, she favored to act as her , for she is dying of cancer. This will mean yukii will act as a bestfriend to kairu, a girlfriend to aiden, and a simone to everyone..