lounge lizard

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun A person, usually a man, who frequents bars or cocktail lounges.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun An idler or pleasure-seeker; a person who spends considerable time loitering in bars and cocktail lounges.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun a man who idles about in the lounges of hotels and bars in search of women who would support him