'Resist Orgasm' works only for 3-4 rounds before it becomes ineffective. I suggest throwing her into a gangbang defeat scene (Solitary Cell or Guard visit in bedroom) when she's really tired and oversensitive after a busy day of fucking. Sensitivity increasing foods also help. That way, one thrust of a dick inside her will be dealing over 50% of pleasure, so one round of enemy fucking (mouth, ass, pussy, tits) may catapult her into outerspace, well beyond the Kuiper belt.Any elaborate tips on how to get the triple orgasm thing? Karen has 114 max energy and that still only gets her to ~240% pleasure before she orgasms.
Also, if playing in Secretary Mode, you may use two in-game cheats that make inmates deal a combined 6x the normal pleasure damage. It's ridiculous, but she'll be able to go from stone cold to drooling orgasm from a single kiss or two.