In my experience, including messing with it in Prisoner mode, the most important stat for Super Slut mode is Endurance, with Mind and Charm taking somewhat equal spots after it.
The higher Karryn's endurance is, the longer it takes enemies to get her to cum even once, and the more time she has to make them cum instead. It also helps ensure that you have enough time to actually use the restore energy skill between orgasms. Beyond that, you need to max out her mouth desire a lot, so you can get the kiss skill asap. The kiss skill lets you compensate for lower charm levels until you can gather the money to buy more accessories that help.
Kiss does two things. First, it helps raise the desire of the prisoners, which helps get them to cum faster, and also gets them hard faster for other sex- skills. Second, it debuffs their attack, accuracy and evasion, which makes it much harder for them to down you before you can get them horny and take the offense to them. Additionally, you eventually get a passive that increases Karryn's Charm for every individual target she kisses in a battle, which means that in longer, multi-wave battles, she stacks up quite a bit of charm, and it adds up even more once you naturally build up the base.
You also don't need to get all of them horny right away, you just need one prisoner horny fast enough to initiate a sex-skill that gets her into sex-mode asap. Once that happens, prisoners can't attack you anymore, and you can use stamina for more sex-skills that get them to cum even faster on top of them naturally thrusting in or against her or whatever.
Top priority accessories for super-slut are the stamina boosting one, and the Endurance one. The mind one helps too, to restore her between orgasms.
You also want the first tier of the Release Desires Edicts as soon as you can reasonably get it.
The best title to use for this play-style is Golden Waitress, the one you get for reaching 30 Reputation at the bar (and yes, that takes a while...). It's super worth it though because it boosts your endurance by 10%, it stacks with training.
Once you really get the build going, you can go an entire fight with multiple opponents without even reaching 30% pleasure, while they all cum helplessly. And that's on prisoner mode.
Also, another thing to note is that defeating prisoners through pleasure gives more Order than beating them down. This is important, because it means you need less battles overall to get more order, and that leaves you more time to do stuff like the Bar Job.