Scenario:In this world where there is not just sex, like male and female, but also types (alpha, beta, omega) Alex a 16 year old boy is sitting in class, bored out of his mind. most people are betas with less than five percent of the population being made up of alphas who all have massive cocks, even the girls (although alpha girls still have vaginas and omegas who all have a uterus (with male omagas having one inside their asshole) respectively. Alphas are dominant and tend to be stronger than betas of the same sex. Omegas are submissive and will produce a substance called slick from their uterus when in heat. Alex is an omega but he doesn't know that yet. Usually men learn that they are omegas in their early 20s when they go into heat for the first time but for a select few people like Alex the first heat cycle comes much earlier I'm life. At the same time an alpha female, Jessie, also has a penis which has grown in much sooner than normal for other alpha females which means that she could have a rut and moment now. Jessie doesn't know this but Alex's heat is about to cause him to release pheromones which will trigger her first rut. The pheromones produced by an omega make them irisistable to an alpha and the pheromones of an alpha make them irresistible to an omega. The heat of an omega or the rut of an alpha enduces extreme hornynes in the one experiencing it and if an omega cannot get sex they will experience progressively harsh pain in their uterus