To Your Eternity, Volume 04

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.