After spending two years in London with his mother, Mio finally returns to his home country — Velvarra, a seemingly ordinary place… until school begins.
Reunited with his distant older sister Rio, who still locks herself in her room all day, Mio dreams of having a normal sibling bond. To get closer to her, he transfers to her school — Aegis High — hoping that maybe, just maybe, he can understand her strange silence.
But something is seriously off about the school.
One class period is mysteriously marked with a ★ symbol, and when it comes, every student rushes to hidden rooms near their classrooms. Inside, Mio sees something no one would believe — an arcade machine waiting in silence.
And when students insert a strange coin… they vanish.
On his turn, Mio hesitates — until Teacher Lily calmly urges him on.
As the coin drops, the arcade machine roars to life. A door opens. And what he sees is not a game — it’s a massive coliseum, a glowing battlefield packed with students from other schools, all wearing strange uniforms, all ready to fight.
A booming voice echoes above: “WELCOME AGAIN, STUDENTS… TO BATTLE PLATFORM LIVESTREAM!”
Now, Mio is trapped in a system where students fight for power, fame, and secrets far beyond the school gates. And the biggest shock of all?
His sister is the reigning queen of the arena.