Mike was still looking down at his new canine erection, even more astonished at this than at Jake's color change. The program didn't seem to have had any problem completing such a drastic change at all. He was seeing on his own crotch pretty much exactly what Jake had between his hind legs, and it made Mike wonder just how far this program would let him go.
It occurred to Mike that, from his perspective, Jake had a really great life in general. Playing with toys, walks in the park, doing tricks for treats. Oh, and just generally being a pit bull. A really intimidating breed even though he was the most adorable softie in the whole planet, he could scare away suspicious-looking strangers with one bark! Mike didn't mind going to work and paying the bills and stuff (MOST of the time!), and he did have a pretty good human life with a decent car and some smoking hot girlfriends here and there, but now that he had this device, he couldn't get the curiosity out of his head:
* Why can't I be the dog for a while? *
Looking through the settings, Mike noticed that he really could pretty much turn himself into an exact copy of Jake if he wanted to, and he could turn Jake into a human just like himself. He could even alter reality and turn off Jake's awareness so it would be perfectly normal that Jake was always the owner and (as far as everyone else was concerned) Mike was always his beautiful black pet pit bull.
At first, he set the duration for one year, and to change them back automatically, but then he second guessed that. Mike was fully convinced he would love being a dog, but what if Jake wasn't cut out for being a human? It would be cruel to make him go through twelve whole months and possibly screw up things even worse in the process. On the other hand, if this went really well and the settled into their lives, a seemingly random date one year later might upend everything they'd come to enjoy at a horrible time, like what if Jake was at work or at a wedding or something?
Then Mike realized, that if Jake was going to be the human, then naturally he was going to be the one with the Chronivac, too. He could change back at any moment in just the same way Mike was switching them in the first place! (Mike should have also realized that Jake could also make any other change, too, and wouldn't know Mike had even been human, but hey, Mike isn't as clever as he thinks he is.) So he didn't set any time limit and allowed the Chronivac to just go ahead and switch him with the pit bull indefinitely.
He ignored the warnings and clicked the final confirmation button, and waited for the change to start.