Four years dedicated to his family have molded Fushi into an approximation of a human. But Fushi's new acquisitions in that low-stimulus life have been few. When he attends Rean's birthday party, Fushi is attacked by a Knocker. Can Fushi, fighting with the help of his brother Gugu, defeat the Knocker and defend his family? This is a story of turning pain into strength.

Volume 4 of the To Your Eternity manga series by Yoshitoki Oima.