Green’s Dictionary of Slang

(US) of a person, soft, weak, effeminate.

1910		O. Johnson Varmint 18: In my country [...] we call a man who uses a brake a candy dude.
1951		J.R. Williams ‘Out of Our Way’ 21 Sept. [synd. comic strip] I don’t like razzin’ from any of you candy comics! [W&F].
1970		Current Sl. V:3 4: Candy, adj. Cowardly.
1990		(con. c.1970) G. Hasford Phantom Blooper 16: It’s my job to keep your candy ass serviceable. I’m the most squared-away buck private in this green machine lash-up, and I will do my job.