We pigs are usually given floor time during cage changing to maximize cleaning efficiency. As it happens, free range time is a prime opportunity to cause mischief.
For example, humans seem particularly vexed whenever we decide to set up camp beneath the couch (read: cavy bunker). Apparently it is difficult to vacuum piggy beans under there and even more troublesome to extract a stubborn pig who always manages to scramble just out of reach.
Belka in particular happens to harbor a deep and devoted love for vertical blinds. Forget regular tunnels, she can spend half an hour at a time zigzagging through the slats at high speed. After expending her energy she is usually content to sit behind the blinds and gaze out at the world.
Thanks to Belka, little Abby-Roo has received the impression that blinds are an exotic sort of cavy toy. She spends much of her free range time slinking through the slats. There is grumbling that replacements are necessary in the near future.
Revy tends to entertain herself by roaming around the perimeter, appearing underfoot when least expected and attempting to eat anything that catches her fancy. This includes paper, soiled towels, other pigs food, human toes and faux leather beanbag material.
The more rascally the rodent, the more lovable. Right?