Stains
A stain is a physical mark on a card — a surface record of contact with a substance. Blood from a fight, mud from a flooded room, oil from a broken lamp. Stains accumulate per substance: a sword can be bloodied and muddy simultaneously, with each tracked separately. They have no scent attached to them and no decay. They sit on the surface until removed.
Stains above a certain threshold begin to affect the comfort of whoever carries or wears the item. Below that threshold, they are descriptive only — the item is marked, and the world notes it, but no mechanical penalty applies. Above it, the discomfort of being filthy becomes real and persistent.
Smells
A smell is an airborne quality that drifts from its source over time. Cooked meat, spilled herbs, alchemical residue, blood — each smell carries an intensity that fades turn by turn, and a comfort modifier that applies continuously while the smell persists at any meaningful level. Smells are entirely separate from stains and are tracked independently.
Where stains are static until cleaned, smells are dynamic. A freshly cooked meal on a campfire carries intense pleasant scent for a short time, then fades. A deep wound saturated with blood may smell strongly for longer. The intensity and the decay rate are properties of the specific substance, not of the object it is attached to.