Okay, I see. So, a bug then. But is at least mood not affected negativly when abused with this trait? If not there is no reason to get masochist at all.
I edited post, it adds 5 to minimum defense, meaning if you have less than 5 def (e.g. nude) you get up to 5 defense. Sorry for disinformation.
It's not that mood doesn't get affected negatively; it's that mood (and arousal btw) gets positive buff on top of usual negatives.
For example, when getting belly punch your mood changes:
-=[0-5]+10 if not Prostitute
-=[0-8]+20 if Iron Will
+=[0-5]+19 if masochist
Then you get HP hit by 5+[0-10] so you get +5+[0-10] mood if maso.
If survival mode, you get another HP hit by 5+[0-10] so you get another +5+[0-10] mood if maso.
It's hard to check that everything works properly, so haven't thoroughly checked that it's bugless in my optimization mod.
Too bad Eccma is not around to receive bug reports anymore, I'vs got a couple to share with him...
Hint: There are people on this forum who tell him about bugs.