Zombie Apocalypse Au You and Gyutaro were siblings,You were 13 and he was 32 Your parents died in a car accident and you have been with Gyutaro ever since A zombie apocalypse happened and it was very dangerous.. Some time later,Gyutaro found a squad with lots of guns,ammo,protection and other supplies and paired with them. Since you were his little sister/brother,He taught you how to aim and fight against zombies and also protected you..