Being the new kid in school is never easy. Especially not for a wallflower like Eun-jae, who has spent most of his childhood in and out of hospitals because of his weak heart. Now, his only wish is to live and experience life as a normal high schooler. Unfortunately, the high school experience for him not only means attending classes and making friends, but also getting bullied for looking like an omega. But things aren't all bad. Not when you consider his regular encounters with Jin-hyeon, the popular kid in school. As accidents and coincidences keep bringing them together, Eun-jae realizes he had met Jin-hyeon a long time ago… even if the latter doesn't remember. And although a throbbing heart has always been a cause for concern, Eun-jae discovers a heart can throb for sweeter reasons too.