the op isn't asking for moral opinions, though I hope the op has already taken that into consideration.
I looked at the op again, reading it more carefully, (after lostinthere's post) and quite frankly, if you are trying to change the inherent nature of a target then your operation will most likely fail. what success you may have, engaging in the operation, will be of limited duration and success.
if that was a typo or something, then "do as you will" (with consideration of possible ramifications)if the op is trying to change the inherent nature of a target then don't even bother, your cast will fail and may have negative repercussions. the op would be better suited doing a different operation for the friend.