I'll do it this way for the time being.
WARNING: Subjects about attempted sexual assault.
Oh dear...Creepy Hollows. Where to even start...
I hope I won't be overwhelming you, but I will be thorough.
I've seen them became niche-ly popular since I was a kid.
Listen, I will NOT sugarcoat it.
They are absolutely a SCAM to begin with! I advise you and your friend to avoid it at all costs! I had my own experiences with them and all are very much downright deplorable. I have a story of my own about such a horrible case. (Which is seen down below)
What is "Spirit keeping"?
It's spirit trafficking. It's an unethical practice of binding and trapping entities/spirits to an object and it's mostly without their consent. They are then sold to a potential buyer, mostly enticed by the idea of sex/romance, money, power, or naively 'friendship.'
The online scam store claimed it's ran by mostly two people -- Mortimer and Magnolia. They misinform their potential buyers with grossly inaccurate depictions of the entities/spirits they supposedly sell, and they clearly don't know what they're doing for one when they actually bind a spirit/entity to an object. Sometimes they just flat out just give you an item with nothing attached to it.
When you get the object with your so-called "dragon spirit," the vessel is either...
-Completely empty (You just bought a random overpriced item)
-A servitor (An energy practice where a being is created without any sentience, but only is created through function, like a robot. For example, it can just play the part of being a "dragon" but it won't be the real deal. It's just pretending to be one. Worst of all, they can become sentient and you'll land with a tulpa instead.)
-A tulpa (An entity created by your own piece of energy with intense consistency and concentration. It's intentions, unlike a servitor, is to have sentience, deviate, and become eventually separate from you. To some, it's mostly a thoughtform that takes on a separate consciousness in your head. I personally believe with enough strength and time, it can be an entity of its own.
Or utterly worse -- an actual trapped spirit/entity.
Additionally, these entities/spirits who they might actually trap are either scared, helpless victims. Or actual malicious beings who will attack you and make your life spiral.
They also have a forum from their store website. However, if you dare to disagree with them in any way, they will attempt to hex you and gaslight you.
As the just the toppings on this rotten treat, they had been using stolen artwork to advertise their "spirits/entities." -- and they resorted to ai art now.
But yeah...all around not good.
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I have two incidents myself involving them, but I won't go too much into it. One is where they created a tulpa, bind him to an item, then sell for someone's demented, sexual fantasies. The being retaliated in horror and anger, and reached out to me for escape. It was a long story...
The other incident is where my friend tested them out and only wanted a reading, but they ended up giving him a supposed bound item with his great great uncle's spirit trapped in it. Luckily, it was just a servitor and the energy within the item dissipated.
Yeah, nothing good comes from them.
I advise you and your friend not to dabble in spirit keeping.
You can work with any spirits without undergoing spirit trafficking.
Just get acquainted with your local land spirits around you, you can even ask another spirit worker to help you personally in finding a companion WITHOUT binding them to anything.
It's like friends. You don't kidnap and tie up people to befriend them.
You let it come naturally.
Good luck...and stay safe.