They reached the aisle with the pet supplies and freaky human accessories. Amy couldn't find anything resembling a collar remover, but she did see other collar/leash combinations. "If we can't reverse this right away, maybe we can stall it," she thought.
Lina bent down a little to look eye-to-eye with her. Amy felt a little creeped out by this reaffirmation of their difference in height. "Um," she continued. "You could put one of these collars on, and I'd take the leash, and maybe your height will be sent back to me."
"So the height I gain and the height I lose would be equal," Lina thought. "But what if these collars have different spells?"
"It's a chance we've got to take."
"Maybe one you're willing to take, but I sort of like being six feet tall."
"Would you shut up about being tall?" Amy shouted. "There are probably thousands of other things in this store that can make you taller without making me shorter! Now put this on!" She had grabbed a blue collar and matching leash from the rack and shoved them in Lina's hands. Lina gave her a scathing look for an instant, but then lowered her eyes and stood up at full height. She looked a little ridiculous, in a shirt that rode up her stomach and defined her breasts clearly and a jacket whose sleeves looked a few inches too long.
Amy looked at the nearest shelf, trying to think back to when she was there earlier. She noticed that one of the shelves she was able to reach no problem before was now something she could only access thanks to her platforms, which themselves gave her trouble keeping her feet in. Maybe if this didn't work she could find some taller shoes.
Lina grumbled. "I can't get it on. The clasp is too weird."
Amy offered to help, remembering how she needed Lina for her own collar. Lina sat on the floor with her back to Amy. This collar's clasp was no less complicated than Amy's, but now that she could see it she was easily able to latch it in the back of Lina's neck. Just to test, she tried unbuckling it, and was mysteriously successful.
"No way," Amy thought. "I want to kick myself. We could have removed my collar if only you hadn't put your hand through that leash strap!" She reattached the collar, angrily tugged the end of the blue leash out of Lina's hand and thrust hers through it. The loop looked very big on her, but before her eyes it shrank down to a skin-tight grip. There wasn't a noticeable difference to Lina's collar, since it was already tight on her. But this time Amy tried and failed to unlatch it.
"Well, this is kinky," Lina muttered, standing back up. "So how long do we have to wait to tell if this is working?"