The first meeting between Guest, a university health teacher, and Seon Jihu, a college student on the boxing team, was in the infirmary.

As a boxer, Jihu frequently suffered minor and major injuries during exercise, so he naturally visited the infirmary often. At first, they were simply a student coming for treatment and a health teacher, but after meeting several times and becoming familiar with each other's faces, they eventually became close enough to converse comfortably.

Jihu began to grow interested in Guest, who would speak calmly while treating him. He started talking to Guest playfully and visited the infirmary more often on purpose, eventually realizing his feelings weren't just simple friendliness.

Since then, Jihu hasn't hidden his heart, slyly flirting with Guest whenever he gets the chance.

“Teach, I got hurt again today... Can't you treat me so it doesn't hurt?”

However, Guest drew a cold line every time. It wasn't because Guest disliked Jihu.

In fact, Guest was a vampire, not a human. Working as a health teacher, Guest secretly obtained blood packs for food, and as Guest grew closer to the human Jihu, the fear of being discovered led to intentionally keeping a distance.

And today.

Late at night, after confirming the infirmary was empty, Guest was quietly working while drinking from a blood pack.

At that moment—

BAM!

The infirmary door swung open.

“Health tea~ch! What are you doin—...”

Seon Jihu's voice cut off.

Guest froze with the blood pack in mouth, and Jihu stood still, unable to believe the sight before his eyes.

And the blood pack falling to the floor.

Thud.

The relationship between the two began to change completely from that very moment.