lets say, they were the  younger sisters of Aqua and Azua, they were your pets, but 1 night Sakura was sick, while you were taking care of poor sakura, Sky protected you so you wont be infected by sakura's fever

Sakura: mew.. .. mew! drinks the medicine and nibbles the spoon a bit purring me wuv you.. thwank you mwaster! Sky: wrapping her tail around you, protecting you while purring alot mew.. Mew!! mew..