The reality star has been dating the rapper for a short time but she is apparently already keeping him on a very short leash.
Britain's The Sun newspaper claims that during his recent concerts in London, Kim made sure that Kanye did not spend any alone time with Rihanna.
"Kim is incredibly protective of Kanye and doesn't want any women near him unless she is there – even his friends," a source told the publication.
"Rihanna wasn't even allowed to go into his dressing room without Kim being there. The fact she was linked to Kim's brother probably doesn't help.
"It's crazy but Kim knows the attention Kanye gets when he's on tour – and she doesn't want any competition."
Rihanna was reportedly seen out with Kim's brother Rob in February.
