The virus waits for the four of them to fall asleep before beginning it's work.
For the two changed just a tweak to the feelings of them
For Biff it did not need to make to many changes, just a sense of the pride being created for her.
For Karyn knowledge of the new pride.
For the other two the changes are much bigger.
For Sarah, the first change is her hair spreading out into her new mane. This is followed by the golden fur spreading over the rest of her body.
Her hands and feet changing into paws. The hands only slightly while the feet all the way.
Around the waist organs reshape along with a tail.
The face is the last to change, the soft human curves becoming that of a fierce lion man.
The new king sleeps soundly on his bed.
Jon's change is even more extreme.
Firstly his chest pokes out into a pair of breasts, but rather then stopping at just one pair two more pairs make their pretense known further down his chest. The corresponding changes also appear between her legs.
Two more lumps grow out from the side quickly forming into new lion legs. Her original legs are pushed out by the new lioness body forming as the legs also change too match.
The golden fur spreads from the lower body up her chest and onto her arms. The hands changing into paw like structures as well.
The head reshapes into a lioness head as well.
The virus looks over the new mother of the pride with a sense of relief that is has solves the problem of the sphinx.