If everyone knows what's at play and abides by the foundational tenants of honesty and trust involved in any kink, bdsm, LS etc. then all is fair.
A stone cold cheating, manipulative, pathological liar that puts everyone in harms way due to selfish risk seeking behaviour and uncontrollable urges is (1) MENTALLY ILL (2) A liability (3) A scumbag no-account, useless lying whore....fuck that noise! And that floppy clam!
A Stupid, Sick, Selfish gash that is committed to stabbing you in the back and try to keep it a secret, then willingly lie and deny their offenses is nothing more than a worthless hole. Extra Hell No points when her own guilt and paranoia get blindly cast upon others to vent the misery in her own head. Again, knowingly and willfully harming others is wrong and unhealthy. it is pure MENTAL ILLNESS, and sociopathic behaviour that ends well for no one, especially the offender.
Get help or get gone! I posses intelligence, self respect and my balls so I know there's always younger, tighter, less insane cooch out there too!