Rihanna Shows Off Her ASSets In Aspen! See The Birthday Butt Pic HERE!

Rihanna technically doesn't turn 26 until mañana, but she's doing some early celebrating with a little cabin fever.

The seksi singer is Staying at a cabin with a few friends in Aspen, Colorado for the big event!

It may be c-c-cold up there, but by the fire it's so warm gurl doesn't even need pants! Which is good for us seeing as how we follow her onInstagram.

RiRi shared the pic (above) to welcome everyone to Ass-pen! We're pretty sure gurl is ready for her birthday spanking!