Click to make it bigger ('cause it's kind of huge):
So, yeah, I suppose I'd better explain all that.
Zwitter is singing along to the chorus of the song "Pussy" by Rammstein, with some minor lyrical changes to reflect zir unique situation. The idea's been in my brain ever since the album came out, and I only just now got around to doing it.
You can hear the song
here. (NSFW because, as you might have noticed, the lyrics are tidbit pornographic. It's still less NSFW than the official video, which is straight-up porn.)
Zwitter likes Rammstein, mostly because they wrote a song with zir name in it. Ze thinks they're hilarious.