Alpha Younghan and Beta Minjae are about to become family due to their parentsā relationship.
While acting as an older brother figure to the troublemaker Minjae, Younghan goes out to buy cold medicineāonly to suddenly witness Minjaeās unexpected omega manifestation. Losing his reason, Minjae throws himself at Younghan, driven by instinct. Younghan tries to run, but he canāt escape Minjaeās pheromonesā¦
In the end, the two cross a line.