smell
Use this tag when something in the picture "smells" (has a distinct odor).
It can be a body part (usually armpits or feet) or an object.
You can tell this if you see:
1. Smoke puffs (put also the tags steam and smoke if it involves sweat, only the latter if there's a fart);
2. Vapor trails;
3. Sound effects (such as "くマ").