Heightened Smell (3.5e Trait)
From D&D Wiki
You have extraordinary olfactory ability.
Prerequisite: Cannot have the Anosmia Trait.
Benefit: You gain the Scent extraordinary ability.
Drawback: You cannot stand strong smells. Any time you are exposed to powerful or bad smells you are nauseated for one round, and then sickened until you're no longer exposed to the smell.
Special: If you ever become immune to the nauseated and sickened effects, you lose the benefit of the trait.
Roleplaying Ideas: The character may get tetchy when a team mate mentions something smells nice.