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. The children were constantly targeted, and if they were defeated, they would die. Makihara and his partner tried their best to defend the children, but years of fighting wore them down, and they had a falling out. Now his partner is back, and he has a demand: put Koyori back to sleep forever, and separate her from Tazuna.

Tazuna and Koyori are facing off against Koyori's sister and the doc's old partner. Koyori's sister has been reduced to an emotionless mute after years of difficult treatments and abuse. Can the two of them bear to hurt someone so close to Koyori? And even if so, can they win against Handshakers who are so much more powerful and determined?