Someone who is so busy using ALL the latest fashion tips and tricks that they end up looking the exact opposite of cool.
You know that guy who lives about a block away from you? The one with the black or red a) Civic b) Mazda 6 Series or c) any Acura? He always has the stereo jacked up to "shrieking"? He wears a tee shirt, with his celtic arm band/ tribal/ barbed wire tat showing? And a puffed vest? Ripped knee jeans? Shades, a hat (or visor) and ALWAYS drives with one arm out the window. Him- he's multicool. I've also heard it called "douchebaggery".
EG, The guys from Jersey Shore are so multicool. That spray tan, too tight t-shirt and spiked hair are so lame.