Rihanna's Hot Shots To Kick Off Her 38th Bday!

Grab your umbrella 'cuz today's Rihanna's birthday -- We've rounded up her hottest thirst traps, and "it's raining more than ever!"

From topless shots to bum shots, the limit does not exist for badgalriri and her shameless selfies ... Look back at it!

How well do you know this hot mama?! Put your trivia skills to the test:

Okay, back to the bed ...

If this is a sneak peek of what A$AP Rocky wakes up to, props to him for pulling such a hottie!

Check out the gallery ... Happy Birthday, Rihanna!