Sophie Rain Covers Her Butt In Frosting to Celebrate Her 22nd Birthday

Sophie Rain's not making wishes on her 22nd birthday ... she's granting them ... and her fans are eating their hearts out thanks to her frosting-covered booty!

The OnlyFans model turned 22 on Tuesday ... and she posed in a really sweet outfit -- covering her backside in what looks like pink frosting, with a spot right between her cheeks reserved for a birthday candle.

Sophie's sexy pal, fitness model Aishah Sofey, got a taste of some of Sophie's frosting ... posing next each other for a sultry snap.

Sophie captioned the clip, "want a piece of my birthday cake?"

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She also shared a clip of herself in rollers, blowing out the candles on her birthday cake -- this time a real one, and not the one she used as shorts.

Happy birthday, Sophie ... and believe us when we say we wanna see many, MANY more.