We flash back to an undetermined time. We're introduced to a prostitute who caught a strange "disease".... one that makes a spike-shaped tumor grow from her arm. However, she didn't take notice of this mysterious illness because she was also pregnant with twins, and their growth drained her of her strength. Eventually, she gave birth to them near a river.... and passed away. As the rats began feasting upon the mother's corpse, the twins were washed away in the river. One year after they were born, a certain famous baby was also born into the world: The "glowing baby" from China.
Soon, it became clear that not only newborns, but also people who've yet to reach puberty gained powers. But as soon as the existence of those with meta powers became widespread, it inevitably led to them being persecuted, and thus began an era of chaos. A few years later, a group of anti-meta hunters run into a young boy.... the future All For One. He kills them all with spikes he grew out of his body,
the very same power he stole from his dying mother! Even at this very young age, he felt that he was destined to rule over all....
However, his younger brother, Yoichi, disapproved of his brutal ways. Apparently, AFO took all his mother's nutrients for himself when they were born, which is why Yoichi is so frail. A few more years later, we see Yoichi reading some comics (which was how he learned to read), while the radio reports news of the grown "glowing baby", who's now fighting to defend peace. As for AFO, Yoichi still believes that he has some modicum of good deep inside him, since they stuck with each other since birth....
Another three years pass. AFO says the "glowing baby" managed to amass
TEN MILLION supporters, but feels that's nonsensical. For as it turns out, fifty people with meta powers (aka quirks) were born in India before the glowing baby. He was merely the first one
officially recognized to have a power. AFO felt he had no right to have so much support if he wasn't really the pioneer he was claimed to be, which is why
he killed him and stole his power! He said Yoichi's comics gave him inspiration to begin his conquest.... particularly the line,
ONE FOR ALL, ALL FOR ONE. He will rule this world through fear....
The last page shows Yoichi running with Kudou (2nd user). However, it seems they get chased by AFO, who ends up killing his younger brother for rejecting him.....!!!!