The Rogue Prince Is Secretly an Omega

Prince Etienne de Frederick was born a dominant omega, but in a world where omegas can’t become the emperor, he must pretend to be a beta due to the empress’s greed. When his childhood friend, Grand Duke Rishar von Eckhart, returns after three years as a war hero, there’s no time to share a happy reunion as Rishar is a dominant alpha and his rival in the fight for the throne. The two continue to maintain a precarious relationship until, one day, Etienne has a sudden heat cycle, and Rishar finds out the truth. “Etienne de Frederick. You were... an omega?”

(Source: Tappytoon)

Note: Season 1 is R15 while Season 2 is R19.