Tazuna is a young boy who loves to fix things. But his life takes an unexpected turn when he meets a girl who's lying on a hospital bed in an electronically locked lab. When he takes her hand, he finds out that he can never let go, or she will die. On top of that, he has to battle a man and his partner in something called the Ziggurat, and he doesn't have a power of his own. Can he unlock the might of the Hand Shakers?

Lily and Masaru insist on fighting Single Gear, despite Tazuna's fervent protests. The two of them use cards: Lily, her Tarots, and Masaru, his precious memories deck. But because Masaru is using the same strategy he does in the game, Koyori knows how to beat him. Can she share this with Tazuna when she isn't able to speak?