The singer is Yui Sakakibara. Besides singing this track, the theme tune to the PSP game Fate/Tiger Colosseum, she has also had a string of various albums and singles and has also been a voice actress for various video games, drama CDs and anime.
If the only thing he'd made was Cillit Bang then I'd agree it's silly for him to be popular. He's done so much more than Cillit Bang though, it's wasily his worst track. I read somewhere that he made it in about an hour.
