I'll try to make a long story short.
While running Jade Regent I added an evil rusalka as part of one of the character's background. The players found the rusalka's prison and killed the rusalka. I later had the PC run into a neutral gnome sorcerer who, during a big boss battle, was relieved to be the 'daughter' of the rusalka.
Some wanted to kill the daughter, some did not. I tried to pull on their heart strings.
Well, more violent heads prevailed, and the daughter wound up cut in half.
Now I have a NPC that some PC want to bring back to life and reason with.
the PC have the Amatatsu Seal, that can bring the daughter back to life and simultaneously alert all the evil Oni in the area to their position.
Since we are playing Jade Regent,
So the PC, being PC, decided not to make a decision and put the daughter's body into a bag of holding.
I decided that Pharasma would not be very excepting of this, and would send a Morrigna Psychopomp after them.
How should I handle this encounter? Any suggestions?
There's some spoilers in the OP for Jade Regent. I'll spoil my answer as it relates to JR
As for Pharasma, why would she not be accepting of putting a corpse in the bag of holding? That doesn't seem like anything she would care about enough to send a psychopomp to attack. Maybe at most send a small sign of displeasure if its her own faithful who are denying a proper burial.
Your Jade Regent point:
Missed that point. *sweeps point under rug*
As for Pharasma, I would assume she would be against not giving a proper burial. I would also assume that she would not like them playing around with a powerful soul (Level 8 sorcerer). How can she give the soul a final judgment if she is kept in a bag of holding to be released and resurrected at the PC convenience?
The soul is in line, awaiting judgment, regardless of what they do to the body. If the judgment has already happened, the resurrection fails. And judgments don't always happen in linear time. I'm guessing the world designers at Paizo probably created that plot device for Golarion so the GM has an answer for why important high level people with lots of money aren't essentially immune to assassination, since sometimes they have already been judged.
Now, if they trap the soul in a gem or make the person into a vampire or something like that, then sure, that messes with their afterlife, and Pharasma is not amused. However, presumably she either doesn't have enough powerful psychopomps or the inclination to send them after such people or else we would have far fewer problems with soul binders and intelligent undead.
That said, if you still want to send a morrigna, they can be an effective harrier. Switch out some of their inquisitor spells known and you can make a great theme, so that gives you room to play with. Spiders and webs fit the morrigna pretty well.