sucker for

a sucker for (someone or something)

Someone who tends to be easily attracted to a particular type of person or thing. What can I say—I'm a sucker for romantic comedies! I've always been a sucker for a guy with a six pack.
See also: for, sucker
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.

sucker for someone or something

someone who is prejudiced in favor of someone or something; someone who is drawn to someone or something. I'm a sucker for a pretty face. Ted is a sucker for any dessert with whipped cream on it. I don't know why I volunteered for this job. I'm a sucker for punishment I guess.
See also: for, sucker
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs. © 2002 by The McGraw-Hill Companies, Inc.
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References in periodicals archive ?
A's Doggie Poop Sucker for 2 years through a collection of dynamic promotional materials such as press releases, product brochures, digital renditions, a password-protected website, and other visual mediums such as a New Product DVD and potentially, an interactive virtual reality presentation.
BARGAIN BUY: pounds 29.99 at Doodle Jump (Sucker Punch, Windows Phone) I'M a sucker for a decent platformer - and they don't come more decent than this.
I've always been hopeless with men and all my family say I'm a sucker for punishment.
Because we know Mom's a sucker for pink, we're giving out 25 free copies.
Orginal's much anticipated song Sucker For A Lover is set to release on October 11th.