Keira entered the barn, she could tell they had mated.
‘Had fun you two?’ she asked.
‘Yes, it was the most fun in years.’ replied Amy.
‘Good news, I still have plenty of formula. Anyone else you want to change?’
‘Bring Jess over here.’
Keira fetched Jess and brought her to the barn.
‘Jess, do you want to be a centauress too?’
Jess pondered for a moment.
‘But I have a ranch to run. You two to look after among others.’ she then looked at Keira. ‘Unless Keira can do all that.’
‘I can run the ranch, I'd have to move my stuff down here but it's possible. The basement can be my new lab.’ replied Keira.
‘In which case I want a test run.’
Amy, Jack and Keira were unsure what Jessica had just suggested as they looked at each other inquisitively.
‘It would take me a month or more to make a reversal formula though.’ suggested Keira, assuming Jess only wanted to be a centauress temporarily.
‘That’s worth keeping in mind but I want to try Jack out.’ suggested Jessica as she started undressing.
Jack was eager for another round, even if this other mate was a human.
Jessica was naked. She went down on all fours to present herself to him. Jack looked visibly aroused as he mounted her.
Jessica felt an intense pleasure as Jack's penis entered her human pussy. It was tight and could feel every part of it.
Both of them came quickly.
‘That was the best sex I have ever experienced! Keira I'm ready.’
Keira passed a cup of the formula to Jessica, instructing her to drink all of it.