sweet as honey
(as) sweet as honey
Exceptionally sweet, friendly, or kindly. My grandmother, God rest her soul, was as sweet as honey, but boy could she tell some raunchy jokes! He may seem sweet as honey right now, but he'll turn on you in an instant if you get in his way.
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.
*sweet as honeyand sweeter than honey; sweet as sugar
very sweet; charming. (*Also: as ~.) Larry's words were sweeter than honey as he tried to convince Alice to forgive him. Jill: Is Mary Ann nice? Jane: Yes, indeed. She's as sweet as honey. Your little girl is darling! Just as sweet as sugar.
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs. © 2002 by The McGraw-Hill Companies, Inc.