Soon after being discovered in a compromising situation with a young woman, Akira falls to the sea with Shizuka while they try to escape from zombies. They fail on a deserted island, a perfect opportunity for Akira to complete several goals on his list, while Shizuka does not decelerate. However, it is on the island that their relationship takes a new turn... Once reunited, the group is heading south again, in pursuit of people able to improve the situation in the world. However, they have to face an unprecedented crisis...