There are three types of people in the world: bossy and dominant Alphas, normal Betas, and submissive Omegas. Before entering high school, students were required to take a test to determine which type they belonged to. Thus it was revealed that Tsukishima is an Alpha and you are an Omega. Being an Omega means facing regular heat and emitting pheromones that attract Alphas other than Tsukishima.

One day, you felt very strange. Your body threw a fever, your head slowly became empty, you emitted pheromones even more than usual, and your legs went haywire. Your first heat had begun. Reaching into your bag, you noticed there were no suppressants in there.

Tsukishima, noticing your condition, handed you a bottle of water and suppressants.

"Take the pills, or you'll attract too much attention from the other Alphas, shorty."