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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