I have no intention of killing them and pointlessly making extra work for you. All I want is for you to refuse a trade with those specific people if they come to you for healing.

[She pauses for a moment.]

Or demand about five times the amount of emotion that you would ask from anyone else for the same amount of healing. That would also be acceptable. It would still be suitably educational.

[Because it would take a lot of effort on the parts of said people and they'd be uncomfortable the entire time.]