Put in simple terms, many animals have a secondary olfactory organ called vomeronasal organ or Jacobson's organ, at the base of their nasal cavity. When a strong smell hits that organ they bare their teeth and hold their breath for a few seconds, which makes it look like they're grimacing or going "eeeeww". It's called "flehmen response".

CinderBH said:

Put in simple terms, many animals have a secondary olfactory organ called vomeronasal organ or Jacobson's organ, at the base of their nasal cavity. When a strong smell hits that organ they bare their teeth and hold their breath for a few seconds, which makes it look like they're grimacing or going "eeeeww". It's called "flehmen response".

Looks like Kaban has some odor issues then.

NegativeSoul said:

Looks like Kaban has some odor issues then.

Nah, the flehmen response only looks like disgust to us. In practice it means more like "hmm, let me peruse this in detail."

zgryphon said:

Nah, the flehmen response only looks like disgust to us. In practice it means more like "hmm, let me peruse this in detail."

Sorta like opening up their "nose" wider to get better focus/resolution on the scent or similar?