louche

Upstairs Downstairs hosts the Kennedys and Wallis Simpson (these days, in British culture, the archetypal louche American).

My uncle knows something about that fellow—Clavering knows something about him. There’s something louche regarding him.

Anyone inside the business can also tell you that without Carine Roitfeld's louche sexy styling Tom Ford's Gucci might easily have come off looking like a high-end Club Monaco.