It’s Miss Wildfire‘s workout day. This means she is getting very sweaty, and so the sub is being put to work to get them clean. 
She starts by having him sniff and inhale the dirty socks – there is a stench from the heavy workout.
Sniffing and smelling the dirty socks.
Now they can come off and the cleaning can begin. Licking off the salty sweat from the beautiful Mistresses feet. Licking the soles, sucking the toes and doing smell tests to see the progress.
Miss Wildfire interrupts to have him smell the socks again – the smell retained from her feet and work out.
She demonstrates the right place for men – under the feet of women.
