Gold Gray

The last surviving omega, and the man who desperately needs him! Fifty years go, a virus sweeps through the world, wiping out all the omegas from the face of the earth. Rain, the sole surviving omega, lives his whole life hiding his identity - until he accidentally runs into Lukas. As the chairman of the facility that used to produce artificial omegas, Lukas has to produce an alpha heir in order to succeed his father's business. And while he has his mind set on winning Rain over, things don't seem to go so smoothly...

(Source: Lezhin US)

Note: Includes 16 extra chapters.