A "peach" is a very common metaphor for a nicely shaped butt.
In "Ménage à 3" (a webcomic heavily influenced by manga) there was an arc where Gary, the bespectacled main character, was trying to decide if he was gay or straight, and this scene happened:
Oh man, that thing is old. I'd forgotten about this webcomic
Yeah, it's been going on for like 10 years. But the end is nigh, as the authors have announced that it will reach its final strip around February. And the two spinoff comics (Sandra on the Rocks and Silly Dilly Buns) will be ending too, more or less at the same time.
I've always loved that comic. I was very active in the fan community at one time... but I have stopped now. The forums are not anymore what they used to be. At one point in time, there were many hundreds of forum regulars, and the great majority were devoted fans who loved these comics. That's all in the past. The Pixie Trix Comix forums right now have about three dozen people who post regularly. Pretty much all of them are haters and trolls. >_< They hate the comics, hate the characters, and most of all hate the happy fans who like what they don't like. The real fans have all left, like me, tired of the constant hate wars.
If anything, when looking at the present state of the forums, one should wonder why the moderators allowed things to reach such a point. The Pixie Trix Comix forums are like a case study of failure in moderation: a once vibrant community turned into a ghost of its former self because of an unchecked inrush of hatedom. Even today, there are offensive posts, insults, trolling, slut-shaming... all under the tranquil gaze of whoever are in charge of moderation, who don't seem to find anything wrong with it.
Oh, and, of course, Giz herself (main author, and owner of the forum) doesn't give a fig either, as she never really cared. Many people complained to her that the forum was burning and the moderators only watched and laughed... and all her replies were along these lines:
Really, we're very very lucky that the admins & moderators here in Dynasty Forum are doing their job properly. I mean, can you imagine if several dozens of homophobic zealots and yuri haters disembarked one day in this forum -- and started flooding the threads with deluges of troll dung, bashing the stories and insulting us loving fans? It wouldn't take long before it'd sink this community, just like it sank the PTC forums. Thank goodness it's not likely to happen.