The Theory of One True Fate (Yaoi)

The following content is intended for mature audiences and may contain sexual themes, gore, violence and/or strong language. Discretion is advised.

At an orphanage, a child appears before Lee Seohu, who refuses to have anything to do with anyone other than himself. The child stubbornly keeps clinging to him, no matter how many times Seohu pushes him away.
Before long, Seohu becomes deeply attached to the child. He gives him the name Yuil—meaning “the one and only”—and begins to bind him to himself, becoming increasingly obsessed with him.
But the world keeps trying to take Yuil away from Seohu in one way or another.
Despite countless crises, Seohu ultimately manages to hold on to Yuil. However, when Yuil suddenly manifests as an all-rounder Guide, the two are forced apart once again.
Now Seohu begins to move once more, determined to make Yuil his and his alone...