My girlfriend lives with her mum, sister and her sisters girlfriend all of whom share a bathroom and a laundry hamper.
When I go over, I go to the bathroom, empty the laundry basket on the floor and select a handful of panties and as I sniff and lick them clean I try and work out whose they are.
My dream is to be able to tell whose they are just by how they smell and taste.
I'm pretty sure I can now tell which are my girlfriends and her mums, but still working on her sister and sisters girlfriend.