The mansion obviously rules (though that's not to say they're always obeyed). The rules are as follows.
1: No killing other members of the household
2: No seriously injuring other members of the household
3: No throwing sharp objects
4: No sliding down the bannisters
5: No summoning beings
6: No smoking inside
7: No damaging the mansion
8: Avoid killing people in the mansion if possible

These rules are supposed be obeyed unless it is strictly necessary to break them.