Imitation Mate

"I just wanted to make an alpha like you pant."

An omegaverse story where an alpha from an elite family who hates omegas meets an alpha who is too carefree. Tsukasa is the ideal alpha: he was raised in an elite family and now works in his father's company. One day, he happens to meet Yoshiki, a fellow alpha and former high school classmate, who he once saw as a rival. However, he is surprised to discover that the aloof Yoshiki is living a carefree, unprofessional life that is completely atypical for an alpha. They go out drinking to celebrate their reunion, and Yoshiki has a few too many, prompting Tsukasa to help him get home. That's when Yoshiki seizes the chance to entice Tsukasa: "Being with another alpha can be fun, too."

Even though he is against it at first, Tsukasa eventually gives in to the frenzy of pleasure and gets carried away in a relationship that isn't just a one-time thing. He figures that he can stop this kind of infertile relationship anytime he wants...That is, until he notices changes within his body...

(Source: Renta!)