@Nephilim02 a banishing chant and some other info. Good luck.
Ashtu malku ta dat arkata Sastus seckz altamu partu
Iretempal krez ta felta Vaskalla regent met senturus
Ta sastrus estos melta Kelta, kelta, ketla hine.
Banishing chant, 3 times in each room for max effectiveness. Use with palo santo and holy water for extra kick. Visuilize your energy forcing the spirit or parasite out.
I recommend going elsewhere to practice banishing and then once you and your friends, have a good grasp on this, get your friend who can see the parasite and together banish him and use the palo santo and holy water.
Then place wards on all the doorways and windows, also line them with sea salt. Put protective runes on them as well. For the runes use olive oil, consecrate it, charge it with your energy and intention.
Also this spirit can help make sure things go smoothly, he can remove it, but its better to learn to do it yourself with a safety net if things go wrong.
https://forum.becomealivinggod.com/t/evocation-guide-for-prince-ragnvaldr/118775/8