Ban Yu-won, who can understand and handle all languages that exist on Earth.
His grandfather had been telling him since he was young:

The master of languages who can interpret all languages,
transform them,
and exert powerful influence through language itself.
We are the descendants of such a great person.
Never forget that fact.

One day, suddenly, the practical evaluation for Union Academy begins,
and after finding traces of his ancestors there, Ban Yu-won decides to enroll in the academy full of monsters.