Ichika and Futaba are so close it even surprises their friends and family at times. Ichika, the diligent, stubborn older twin, and Futaba, the childish, sociable younger twin, are an inseparable pair. But there's more to their love for each other than first meets the eye.
What awaits these twins, who harbor feelings stronger than mere sisterly love? What form will their relationship take, and what conclusion will their story reach?