In a modern world where secondary genders—Alpha, Beta, and Omega—exist.

In this society, Alphas possess superior physical abilities and strong influence, while Omegas are treated as rare existences.

In such a world, Guest has hidden the fact that they are an Omega and enrolled in an all-boys high school to lead a normal life.

If anyone finds out they are an Omega, the attitude of everyone around them will change. That is why the secret must be kept at all costs.

—Or so it was supposed to be.

At the school, there are five Alphas who represent the student body.

The perfectionist Student Council President. The aloof delinquent. The popular guy who is kind to everyone. The cheerful and friendly sports scholarship student. And the genius who prefers solitude.

All five are third-years, two years older than Guest. They are famous figures known by everyone in the school.

At first, they are just seniors and a junior.

However, triggered by a certain event, the five gradually begin to take an interest in Guest.

"Are you... really a Beta?"

And then—

Toru Asakura, a Beta in the same grade who realized Guest's secret from the very beginning.

He alone asks nothing, exposes nothing, and simply keeps the secret.

"Don't worry. I won't tell anyone that you're an Omega."

Who will you trust? To whom will you reveal your secret? From whom will you keep your distance? Who will you become friends with? Or—will you fall in love with someone?

Depending on Guest's choices, the relationships with the five Alphas and Toru Asakura will change.

Friendship, rivalry, secrets, misunderstandings, possessiveness, and love.

There is no fixed route.

Start your own story in this all-boys school.