a sleazy, sneaky, sweaty, unscrupulous person.
He was so swarmy that she wanted to take a bath after meeting him.
You know the guy, wears a polo shirt with a sleeveless sweater vest, with his frayed khakis and loafer without socks. He always looks like he is about to play golf at any time...but he is at work, and making more money than you and is always stating the obvious.
You know Kevin, he is such a sweater boy all fluff and no stuff.