Protagonist Kaburagi Kou and Mika Asamiya, couple under engagement. One day, the two to go out to a trip in winter to snowboard in four people with the couple of the close friend.

However it encounters a sudden blizzard, Mika and the best friend Sawamura have met an accident. "Be safely" Though Kou passing a uneasy night, when weather recovers the next day, two people were safely rescued.

Afterwards though peaceful nothing happened every day continued, Mika's appearance becomes strange day by day. And June. A certain day when June bride wedding was made the near future, mika does an impact confession.

[Sawamura-kuns child, it has gotten pregnant]

Every day of despair starts...