Psychic and Paranormal
I wish I had more experience so that I could tell you why you have that affect on the entities and your friend, but I don't.
If you suspect that your friend has an attachment, I wouldStrongly recommend shielding yourself and possibly hauling ass to the nearest crystal shop and buying yourself some black tourmaline and amethyst (others may have other recommendations who are more knowledgable-take their advice - I say black tourmaline because it deflects negative energy and psychic attacks and amethyst because it repairs holes in your aura;holes in your aura make you much more vulnerable to attachment).
I'm a recently awakened empath but I have been either seeing, hearing, or feeling/sensing spirits since I can remember.
When I was around 19 and 20, I was terrorized by a demon for what felt like an eternity but a year or so, give or take a little time.
I sound a little extra cautious not because I want to scare you but just because I think it is important to listen to your instincts and to keep yourself grounded.
As for your friend who you think has an attachment, I wish I could tell you what I did, but I actually never had an exorcism, or Reiki, or anything performed on me...to this day, I thank God, my Guardian Angels, Spirit Guides, the Archangels...when I was at my lowest point and about to completely crumble, divine white light came down upon me - I didn't see it with my regular eyes, even though my eyes were open, but it was still very bright! And I heard a voice in my head tell me that it didn't have to be this way! that I was a good person and that I could rise above this,
and I did!
My point is that I feel very blessed and grateful, and I greatly want to help your friend but I don't have any firsthand experience with having had an attachment removed from me.
I have been told, however, that a Shaman, a priest trained in how to perform an exorcism, a Reiki Master - and I have heard that the crystals Stillbite and Aegirine are what they would use to extract attachments - you would not want to try this yourself though!!!!
Sorry for this incredibly wordy response. I hope all of this helps you and your friend, though! Good luck and please let all of us here know how things go:)