The only dominant sex act right now is footjob and that requires a rather high cock desire which makes you vulnerable to other type of sex acts as well so unless you cheat it will be difficult to just get the footjob. The rest of the sex acts, Karryn is clearly not in a dominant position. I originally wanted to make Karryn a Dom as well but quickly realizes that it will take too much effort for too little satisfaction. At the end of day like Pailbat said, this game is about a strong prudish woman becoming more and more like a whore the more time she spends at the prison.
A high Charm and Agility build can sorta pull it off. She stands there posing and taunting while the prisoners masturbate helplessly in front of her. Slut level shoots up to about 20 iirc but doesn't go much higher than that because you avoid actually having sex with any of them.
And you can get most of the sadism points by just using Taunt a lot, waiting for your pleasure to get high enough, then smacking some of them around enough to finish yourself off (avoid actually using your halberd when you're not at the level cap though, or it will advance the wrong stats and lower your max charm).
If you want the footjob skill, don't let your cock desire get too high with any of the other enemy types or you'll find yourself giving out handjobs, but if there's nobody but Nerds around and you keep all your other desires low, they'll usually ask for a footjob instead of anything else. Do that on five different nerds and you should get a passive that lets you do it voluntarily to any target who's blushing.
in the receptionist work, there is a way that "something interesting" happens like in the bar tender work? or is just a goblin fapping on her?
At first, no. But if a visitor sees you doing something lewd (they have to be standing in line at the time), they might get a little exclamation point over their head, and at the end of the shift that raises your notoriety. If they see more lewd stuff while they have the exclamation mark, it changes to a sort of blush mark (and every point of Notoriety you have gives a random chance that your fans will arrive with a blush mark instead of their usual sparkle); every time somebody with a blush mark comes to your counter they show a nude picture instead of the usual silhouette and instead of a handshake they request a kiss, or a grope, or a handjob. Normally the desire requirements to accept are well above 100 but with enough passives (either the normal kind or the ones you get from the waitress job that apply specifically to side jobs) will get you to where you can agree to their requests. And if there's somebody waiting behind them in line while you get them off, they inevitably see enough to get horny themselves, and you can repeat the performance until you run out of visitors.
Note that if somebody did actually come here for a reason, they'll go through the same paperwork process as a normal visitor after you finish with them, and you can only do lewd stuff when you're first greeting them; when they come back to turn in their finished forms they'll still be naked but act all businesslike.
Also, tragically, female visitors never get past the exclamation mark stage. Even the ones who are fans and came here for no reason other than to see you will wait in line watching you jerk off two men in front of them, come up to your semen-soaked desk while you have a whole goblin up your butt, and just ask for a normal handshake.
And as far as I can tell there's no way to get anybody other than a goblin behind the counter with you, and no way for you to leave your post or get on top of your desk, so you can only interact with one visitor at a time and only with your upper half.
There doesn't seem to be a title or passive for orgasming from a handshake alone either, which seems like a serious oversight to me.
Edit: it occurred to me that I'd never actually 'lost' at the receptionist job by running out of energy, so I just tested it and even if you fail out of your shift completely the goblins just drag you into the bar's storage room. So there's no way to play with the visitors beyond a blowjob. Can't even unbutton your shirt.