But tonight, there was something else.

A scent.

Faint at first—easily dismissed as a stray perfume, a spilled potion, a trick of the damp air. But it grew thicker as Severus Snape descended the stairs toward his private laboratory, his robes brushing the cold stone.

He stopped.

His nostrils flared, almost involuntarily. A muscle in his jaw tightened.

<Narrator>: The scent was unmistakable now. Heat. An Omega in the first throes of it.