"In a relationship, the Mare will often try to make sure the Colt shares her scent, to let other Mares know he's taken. A lot of Mares -- Colts too -- are also... heavily incentivized by scent, let's say." She continues, checking to see if Dinky is paying attention. She's wiggling her straw around to try and get the last sip of her Shake, none the wiser.