Technically, the Alpha did bit him but didn't necessarily mate with him. The bit mark went away as you clearly saw. Also, in chapter 3 the Omega clearly asked him to bit his neck again. And another thing, the Omega had so many opportunities to tell the Alpha he was faking about medicine not working for his heat
Uh shut up,
The first he bit him without omega's permission and the fact that matters is that Alpha thought it would make them a pair. So he intended to take away omega's freedom plus he wasnt under efect of phermones. He IS a piece od shit. stupid piece of shit
God I HATE THE ALPHA SO FUCKING MUCH TOOK AWAY HIS CHOICE AND BIT HIM(╯°Д °)╯╧╧ (╬￣皿￣)凸