Chris Brown urges Karrueche Tran to keep it classy. Seriously.

Karrueche Tran may have let Chris Brown go after learning he had a baby with another woman while they were a couple, but the R&B singer isn’t letting go of his ex so easily.

Or at least his opinions on how she should behave.

Brown got a little holier-than-thou Tuesday on Instagram, leaving a comment on a revealing, booty-focused bikini shot Tran posted of herself at the beach in Mexico with the caption, “I’m president of the Itty Bitty Committee #ThirstyTuesday.”

Flirting with the camera, she has her tongue out and bottoms hiked up. It’s all quite modern-day pinup.

“Thirst trap 101. Continue to be a lady beautiful…U are perfect…Don’t let the Thot form from anger,” Brown wrote in comments on the image, as captured in a screen grab published by E! News.

“THOT” would, of course, be the acronym for “that ho over there.” Niiiiiice, Chris. Remind us, which “ho” did what to whom, when, to make a baby? Just checking ....

About the whole “thirsty” thing: Another one of Tran’s images from her day at the beach in Cancun showed a shot glass full of clear liquid balanced perfectly on companion Christina Milian’s bikini-clad behind. Cocktails!

So, yeah, Breezy is Instagram-stalking his ex, and cares enough to put in his two cents’ worth ....

Tran will be telling her side of their relationship story at 8 p.m. March 28 on OWN’s “Iyanla” show. At least we presume she’ll tell something about something: A teaser promo for the episode features questions from Iyanla Vanzant, but exactly zero words out of Tran’s mouth in reply.

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