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!
Tazuna and his new friend Koyori have a problem: If Tazuna lets go of Koyori's hand, she'll die! Can he take her home with him and explain to his parents why he now has to live with a girl? And how's he going to take a bath with her!?
Tazuna meets Chizuru and Hayate, the pair whose car he fixed on the day he met Koyori. They're workers for a major food corporation in the area, and they offer to treat him and Koyori to dinner as a thank you.
Koyori gets separated from Tazuna, and because she doesn't have a cellphone, she doesn't have a way to get in touch with him. Fortunately, she's found by President Lily and her little brother Masaru, who take her to play a new game.
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.
It's time for the School Festival, and Tazuna's class is in big trouble! Can Tazuna use the connections he's made so far to make everything right? And can Koyori learn to cook in time?
Tazuna and Koyori meet their next opponent: Kodama, a powerful idol singer who has defeated many other Hand Shakers. She and her producer are their toughest opponent yet, and together, they overwhelm Single Gear.
Tazuna and Koyori battle Awaza Kodama a second time, and she's just as powerful as the first. Tazuna, and Single Gear, cannot hope to defeat her. Their only choice is to rely on Koyori's unseen strength.
With the last of their foes vanquished, and Koyori now having the ability to talk, it's time for her and Tazuna to take up a part time job. It's a time to reflect on what's gone on so far, meet old friends, and ready the pair for the future.
Makihara once had a partner, and a boss. Together they researched the Ziggurat, and the mystery of Babel's revelations. But when a pair of Hand Shaker children were born, their lives changed.
