Initials standing for Jack the Lad Swing, used for the crappy boyband that is the bratty little love child of the X factor, a UK singing show. The 4 boys involved are only famous because pre teen girls fancy them all and dream of marrying them, not due to any real musical ability or singing talent. They spend their time bringing out condoms with their names on the to make sure teens 'Just Love Safe' not actually writing meaningful lyrics of their own. For example their lyrics to the song 'Everybody in love'-
Every minutes like an hour,
Every hours like a day,
Every day lasts forever,
I’d wait forever and a day for you.
According to their system they'd wait for an hour and a day for their girlfriend and then bugger off.
Jenny: OMG I love JLS! I'm seeing them in concert.
Alice: Shut up, you wouldn't like them if you didn't think they were fit. They can't sing anyway.