DESCRIPTION
It looks like Katara made Toph curious about foot fetish, she was feeling so much pleasure from having Katara's tongue between her toes! she now needs to taste feet herself!
Katara is so happy for this but she feels shy, she wasn't ready, her winter clothes and shoes made her feet quite sweaty. But Toph doesn't care, maybe her enhanced senses and love for barefooting made her prone to foot fetish.