Unconventional Omegaverse

Alpha x omega
- Respectful alpha
The alpha doesn't force himself upon the omega even though he's right in the middle of heat. The reason is he can't feel pheromones like other alphas.

Beta x alpha
- Unique pairing
An alpha cop gets attacked in an alley and injected with a drug that makes him go into a rut. Alone on the street and not knowing what to do, he gets saved by a beta doctor who takes him to his place and "helps him out" with the rut.

Alpha x omega
- Unique world
Although the manhwa in terms of the characters isn't all that unique, you got your typical dominant alpha and submissive omega, I think the world-building is pretty different from the usual ABO story.

Alpha x omega
- Respectful alpha
Although the alpha comes off a bit douchey, he doesn't take advantage of the omega sexually or anything. Everything is consentful (at least when it comes to the seme). The omega Yukishita gets mistaken for an alpha due to his appearance and he's never experienced heat before despite being in his 20's, however that all changes with the alpha Renjaku who Yukishita has a massive crush on.