Mika Sakakibara, who declares "It's impossible for women to be together!", accepts a challenge from Aya Fuwa, who says, "Then let me test whether it's impossible for women to be together or not." They decide to compete for 100 days with a wager of 1 million yen, spending 10,000 yen a day. As Mika spends time with Aya, her conviction that it's "impossible" gradually weakens. Will Mika be able to insist that it's "impossible" even after 100 days?