Rio has safely completed her shift with the petri dish. She is too serious, and her teacher tells her that she needs to be energetic every once in a while, so she decides to have sex.
After being caressed through her tights until she melts and made to cum by cunnilingus, Rio starts giving him a handjob as instructed by her teacher. She takes his huge cock into her mouth and swallows it all, leaving no drop behind!
She releases her huge breasts, worthy of the name of a big sister, and leads him to cum with a titjob, and then it's time for the real thing!
She arches her back and trembles as she climaxes, exposing her face in pleasure at the pleasure of raw sex without a condom. What will Rio's answer be after such a furious series of orgasms...?