Well as it's says the blood thing it's just for show if i can say that
In my opinion it doesn't really matter.
Can't you do the ritual when they're not home or something?
Well you will have to agree with the mission or not, think carefully about it. i don't think they're going to FORCE you to...
and maybe now /perhaps/ i won't get 200 mails/day with senseless questions... i don't even have enough patience to read them all.
hope this clears the problem.
Ave Satanas!