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Officially translated as "Are You Lost?", the original title read straight literally means "Is that so?", but the "sounan" can also mean "stranded".
A manga about 4 girls (and another set of classmates and the main girl's father) forced to survive when stranded on a deserted island by an airplane crash. The story has a focus upon the details of survivalism, such as how to find water, prepare shelter, secure food and cook it without any manufactured tools available.
Major characters:
Onishima Homare - (Short blonde pigtails) Survivalist nut that teaches the others.
Amatani Mutsu - (Short red hair with glasses) Level-headed honor student.
Suzumori Asuka - (Short brown hair and large breasts) Energetic student athlete.
Kujou Shion - (Long blonde hair and hairclips) Sheltered rich girl.