The light blue one

"What does the blue one do?" You ask and Kruya takes the small bottle out of the case. "It represents the crow's talon you found. It makes you grow smaller than normal. This amount will make you an inch tall. This is very dangerous, so I advise caution. You'll grow back in a few hours of course."

You don't think about it as pervy at first, but start getting ideas and blush hard.