After reading some of these, I'm suddenly very glad I got my sims a Bonehilda. She's so far been very good about keeping the house tidied, though she doesn't pick up laundry. I have seen her walk into the bathroom while they were using it and not be embarrassed about it, which is doubly funny since both of my current sims are supernatural (a male witch and female fairy, brother and sister). Guess they're just use to Boney being around...
As for her little quirks, so far I've seen my Boney dear do an arm flexing pose (she's Athletic?), frequently check herself out in the bathroom mirror, clear dishes, clean the toliet, and make beds (definitely Neat). My sims have yet to chat her up since they're both working on getting skilled up to reach their LTWs, but I'll be trying that out as soon as I can. I'm hoping she'll be good with kids since I'm planning to marry off my man-witch to a townie who's got a child and another on the way...
In short, I really recommend getting a Bonehilda just because she's a nifty addition to any household.