That B*tch has photos of Rihanna hiding her mouth from the paps -- and for good read reason. She has a canker sore (otherwise known as an Aphthous ulcer) on her lip and she doesn't want you to see it.
Canker sores can be rather unsightly and distressing, particularly to women like RiRi who rely on their looks for their livelihood.
Now the messy ones among us want you to believe she has Herpes Simplex (a cold sore). But I doubt it.
An Aphthous ulcer is a very common, recurrent skin condition that is not contagious like Herpes or MRSA. Almost 10% of the population suffers from Aphthous ulcers -- mostly women. The cause is unknown.
If Rihanna does have Herpes, we wonder where she got it?
Looks like Chris is wondering too.