That is why I said the order of calculation may have changed. If the +2 is added before the -1, that means the NPC started with 100 happiness, +2 (except it won't since she is already 100 happiness), and then the -1 is added, which ends up with 99. If the +2 is added last, it will go 100 - 1 = 99, then +2 gets her to 100 because it caps at 100.
This is still in the alpha (0846), so we will have more information once it is done testing.
Can you get her to the bondage room? How's your bondage/flagellation skills?
At a certain enough level of corruption, she will continually gain arousal from just you randomly clicking around in the dungeon, without doing any action. You can click Stimulate and then Back, over and over without clicking any actions in the Stimulate options, and she will gain arousal. Once she is at 7 or 8, press Caress Pussy in the Stimulate options to get her to 9. Then do oral, get her to Deepthroat once and you should see her orgasm and gain +1 Affection and +2 Corruption. Pull out, get her to 9 Arousal, oral sex, deepthroat once. Repeat until you cum. You should get +6 reliably per session.
Anal hook is semi-reliable with +1 Corruption, if you want to do something all day instead of waiting on your libido. Honestly, though, with Evercock implant, you might be faster with the deepthroat method.