Bareback whenever possible... KK has a cum fetish, loves the wet, slick feeling of bare skin on skin, and the sensation of being filled with cum.
There are practical issues as well; she's got a mild latex allergy, and situations arise where we're without our favorite non-latex condoms (Skyn). Condoms also increase friction injury during extended sessions.
Our protocol in general is to have all partners screened for STD's, but occasionally, usually driven by opportunity and circumstances, this guideline gets ignored - KK will fuck bareback "in the moment" if she's sufficiently in lust.