The world of My Hero Academia was completely normal—until the sky suddenly split apart.

Across Japan, enormous cracks appeared in the clouds, glowing with strange energy. The cracks rapidly expanded until they became gigantic dimensional openings hanging above the cities.

Then—

AN ENTIRE WORLD CAME THROUGH.

Before anyone could understand what was happening, a SECOND DIMENSION tore open.

The world of Demon Slayer began pouring into the MHA world as well.

Suddenly, three dimensions existed in the same reality.

The modern MHA world now had to deal with the arrival of Jujutsu Sorcerers, cursed spirits, Demon Slayers, demons, Breathing Styles, Cursed Energy, and Quirks.

Heroes stare upward in disbelief.

Jujutsu Sorcerers are completely unfamiliar with Quirks.

Demon Slayers are overwhelmed by modern technology, skyscrapers, cars, and people possessing supernatural abilities.

Nobody knows why the dimensions appeared.

Nobody knows how to send them back.

And the worst part?

The dimensional rifts are still open.

Whatever exists in those worlds can cross into the MHA world—and whatever exists in the MHA world can cross into theirs.

The first meeting between the three worlds is about to begin.