A magician, a female doctor, a gangster, an archaeology professor, a policewoman, a drug dealer, a businessman... Such a random group of people find themselves trapped on a desolate island when they wake up from sleep one day. They are surrounded by tribes, mutant viruses, and countless life and death situations on this mysterious island. What will they do to survive and escape?

Maiku Kamishiro's past has always been somewhat of a mystery to him. The only clue he has to who his family might be is an old photograph showing two young children, a boy and a girl, playing in a small pool outside of a blue house. In an attempt to find his family, he moves to this blue house and begins working as a programmer. He's living a comfortable life until the day two very different girls show up at his door, both in possession of the same photograph, and both claiming to be his twin. With no way to prove who is a relative and who is a stranger, Maiku allows both girls to move in with him until they know for sure. 

(Source: ANN)

Saeki Koushirou works as a wedding planner, but his own love life is in shambles. His background makes it difficult for him to commit himself wholeheartedly to love. The child of a divorced couple, he lives with his father. He has a mother and a sister, but he has not seen them in years. After being dumped by his girlfriend, a chance encounter with a female high school student shakes Koushirou's calm and awakens new feelings in him—but he learns that the girl is in fact his sister, who will now be staying with his father and him. Yet, the feelings in Koushirou's heart... (Source: ANN)

Shinobu Oomiya once left Japan to participate in a homestay in England. During her time there, she became close friends with Alice Cartelet, the daughter of the family she was living with. However, when it was time for Shinobu to return to Japan, the two were able to express their sorrow despite the language barrier between them. Five years later, now a first year student in high school, Shinobu receives a letter by air mail in a language she does not understand. This letter is penned by none other than Alice, detailing her own homestay in Japan. In fact, Alice will be attending Shinobu's high school and living with her! Alongside their friends Youko Inokuma, Aya Komichi, and Karen Kujou, the five girls attend school together and learn about what their different cultures have to offer, day after day. [Written by MAL Rewrite]