"D-don't tell me you imprinted?!"
"No, I didn't. I only bit you enough for you to calm down."

Hyojae, an alpha, bites Taemin whose heatcycle started, and Taemin turns into an omega.

Although he bit him lightly, does it mean he's imprinted?
It deeply influences their feelings and thoughts for each other...
Both of them start to want to confirm if these feelings are due to pheromones or love.

"Choose. We'll live together forever or live separated from each other, there are only two choices."