Naruto had no choice but to kiss her foot. As he kissed it and got a hint of its taste, he knew he didn't want to do this anymore.

Then Katara said, "Kiss it until I told you to stop!" Naruto didn't want to have to taste her foot again, so he kissed it lightly.

As Katara notice about Naruto kissing her foot lightly, she stomped her foot on his head ,hard, and kept his face on the ground with her foot. Then she said, "You better show some appreciation while kissing my feet, or I'll torture you worse!!!"