After three months of being human, Sally had come to two conclusions. One was that being human was awesome. Sure, she missed the sensitive canine sense of smell, and some things, like having to put on clothes every day due to a lack of fur, were tedious, but humans had such a broad range of possibilities and choices denied to dogs.
The second was that human beings were idiots. God or the gods (religion was one human thing Sally was having a hard time getting the hang of) had given humans the greatest gift of all--perpetual heat! And yet humans wasted an enormous amount of time doing other things when they could be having sex! And they had this weird thing about not having sex in the presence of other humans, something a dog would never even think about! Sally was having a lot of sex with male and female humans, but she couldn't help feeling she was missing opportunities due to the sheer stupidity of her new species.
In the mean time Jessie was experiencing her first heat. Sally didn't quite understand what humans meant when they said "feeling guilty" but she did on some level think that she owed Jessie the satisfying canine sexual life she herself had never had. She remembered the agony of sexual frustration. She was thinking about what male dogs were available when she realized that with the Chronivac she could (temporarily) be that male dog herself! And experiencing sex as a male would be an enriching (not to mention fun) experience! Males did seem to be a lot more open about their enjoyment of sex.
Sally input "mature male collie, three hour transformation." She mumured "won't be long now, Jessie-girl" as she felt the first changes sweep over her.