That is a good question. I just bought a new pair or succubus wings, tail, and horns for my last cute and cuddly gf to wear... For science of course.
As for your videos, first, I would suggest you giving this one a watch. It's a ritualpasta called "A ritual to find a date for Valentine's Day" on Youtube. I think it will help set the mood for you to really think about what you want in your succubus gf.
As for her, there is a video called "Succubus Summoned" on Pornhub. That might convey the tone you are looking to bring out of her if supernatural horror is your desire.
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