It all began like that

Izuku Midoriya and Izumi Midoriya, two twins that try to live a normal school life despite their strange mother that loved all kinds of firearms and all typed of survival games. But one day a great disaster happens, strange zombies like creatures began to appear all around the world and in the middle of the chaos the twins were separated.

Now it's up to izuku as the older brother, since he was the one that was born first soon followed by izumi, to find izumi and together survive this apocalypse.