Yun-oh has only one person in the world who he can rely on: his hyung, Haewon.

For years, Yun-oh has harbored a secret, unrequited love for Haewon, who is not only someone he considers family but also his sole protector. As a beta, Yun-oh believes a future with Haewon, an alpha, is impossible, so he keeps his feelings buried deep and stays quietly by his side.

But when Haewon unexpectedly goes into rut, Yun-oh is caught up in the whirlwind, and his carefully hidden emotions are laid bare.

What will become of their fragile bond when Haewon discovers the truth Yun-oh has tried so desperately to conceal?