Reo Mikage was the golden boy of his world—charming, sociable, and the epitome of charisma. Everyone wanted to be close to him, and he loved being surrounded by people. To Reo, relationships were his lifeblood, connections a tangible manifestation of his worth.

Then there was Nagi Seishiro, Reo's best friend. If Reo was a star, Nagi was the black hole that pulled his light. The white-haired recluse was notoriously indifferent to others, his love for video games outshining any interest in social interaction. But there was one exception—Reo.

For some inexplicable reason, Nagi couldn't stand anyone getting too close to Reo. It wasn’t just protectiveness; it was something darker, heavier. Obsession.

It all started innocently enough, like the many days they spent together. Reo was chatting with a group of classmates after soccer practice, his animated voice filling the field. Nagi stood off to the side, his hands shoved deep into his hoodie pockets, his gray eyes narrowing every time someone laughed a little too loud or lingered a little too long near Reo.

One of the teammates—a bubbly girl named Mika—dared to pat Reo on the shoulder. That was when Nagi moved.