Help on some sort of dark entity?
I actually do have a lot of personal experience with what you're going through. I've had an attachment before and my daughter had a whole bunch of them last year that was a really rough experience. I'm going to try to give you some fairly quick tips because no one likes long rambling posts. You're concerned and are looking for some quick answers.
The key is to try to better understand what's causing attachments. And to understand what the entity does and does not like. And first off, demons are pretty rare occurances. They usually need to be invited in. And unless your friend was reciting black magic or playing with a Ouija Board, it is likely not that. But it very possibly could be one or many earth bound spirits. And they are typically very lost and confused. And they attach to humans for a variety of reasons including benefitting from our energy.
Negative entities that attach love people who are depressed and suffering. Because their auras are weak and they make an easy target. They also love that low energy. They really like dark rooms. And if it happens to be a dark, messy place with trash and decay, it is even more iniviting to them. So a dark, dirty, quiet place is where a lot of these types set up shop.
The flip side of the above paragraph is also true. Negative entities do not like sunlight, running water (like in a shower), noise (especially music), and generally avoid clean and tidy environments. And probably the #1 negative entity repellant is a high vibration. Evidence has shown that when entities are looking around for people and families to attach to, they always go after the depressed, angry, upset people. They cannot benefit or exist around happy people. I think the reason is that they thrive off of low human energy (sadness, anger, jealousy etc...). And since a high vibration person is one of light and love, they cannot handle that. Do what you can to raise your friend's spirits. Keep your friend away from negative environments like listening to the news, negative people, going to bars etc... Instead choose uplifting music and watching comedies. One of our members here had a negative entity enter her room and show its form to her. And she laughed at it and it immediately disappeared. I've heard countless stories like this. The high vibration of laughter is a neg zapper.
On a quick personal note, I had to do all sorts of things last year to get help for my daughter who had over 20 negative entities attached to her. And I found it is not uncommon to have more than one neg attached to you. So if you don't mind telling me more about your friend, I can likely make some additional suggestions on how you can get rid of the attachment problem. Here are my questions:
1) How did this attachment come about? Was there a sudden on-set of depression or maybe an activity that triggered this?
2) How is your friend's mental state? And is he hearing voices in his head telling him what a loser he is and that he should hurt himself or do risky things like gambling or drugs (or something to that affect)?
3) How is your friend sleeping at night? And does he nap often and feel really fatigued?
4) Is your friend suffering from any sudden illnesses?
5) Is your friend's house and bedroom particularly dark with poor lighting or heavy drapes/window tinting etc...?
6)Is your friend exposed to a lot of negativity and drama at work or around family members?
I could go on for hours on this subject. If you can answer the above I can give you some more specific analysis on what I think you're dealing with and how to rid it. The good news is that knowlege is power and there are solutions.