This is set in the Omegaverse. The Omegaverse is an alternate universe following the hierarchy of wolves. That is to say, the alpha, beta, and omega. This system is what also gives it the name
"Omegaverse" as well as the short term A/B/0. Alpha's are the highest rank/type in the omegaverse. They are very protective of what's theirs and can be highly aggressive. One key thing of Omegas is their heats, this is a time when their sexual arousal is through the roof and their scent glands are potent.