Resized to 85% of original (view original)
Artist's commentary
Peachybutt? Momiji Butt?
Take your pick....
The second one, that's Momiji-chan too, after she has fallen out of a tree.
The title is referring to the fact that Momiji's head in the first picture is obscuring the Kanji, so you can't quite tell what it is. "Peachybutt", according to google, is a fat ass that sticks out quite a bit, resembling a peach.