Insatiable by Darren Hayes.
For old times sake, I've uploaded the song on the sidebar. It reminds me a lot of being in school. Used to sing this when we took our baths around the water tank behind the school hall. If I'm not mistaken, Avril had her famous debut with Skaterboy at that time.
It was pathetic trying to sing this because I was an octave short but I sang anyway. Hey, it was "bath time". You just had to sing.