Remi and Hina's Phase Connect smell tier list.
I didn't watch so I have no idea how Rie, Runie, and Muyu managed to get below Pippa on this. I think the reasoning for Airi is "wet dog".
EDIT:
Yeah. Remember that before lesmaxxing and 86 cubs, the meme for Uruka was "trash bear". And she actually did have trash like old McDonalds sauce packets lying around her desk that could be seen in handcam streams.
Something I remember from my college days is that college is a time for young'ns to learn proper hygiene (I myself was no exception). There's practically no way the college-aged Uruka doesn't smell at least some of the time like piss and crotch sweat.
Not that it's impossible for someone Airi's age to smell the same, as I have met people my age who still smell like a cup of spoilt yogurt. I'll just assume the ponwolf smells like Dove soap for sanity's sake.