大海原で漂流してしまった少年・東方院行人がたどり着いたのは女の子ばかりの藍蘭島だった! Ikuto Touhohin just had a last fight with his old man, one that led him to make a rash decision to run away from home. He boards a ship, deciding to take a vacation, but the ship is suddenly hit by a huge storm–one that sends Ikuto overboard! When he regains consciousness, he realizes he is still alive… on some island. An isolated island. An isolated island with nothing but girls and talking animals. Stranded on an island with only girls, no electricity, gas, radio, television… like he was back in the stone age.