They can bring a different type of adjustment; sometimes causing nightmares, bad luck, overwhelming physical reactions such as headaches or joint aches. For most these subside in the first week, sometimes up to two weeks. They aren’t evil or out to cause problems. As previously explained being classified as Dark Arts means it can choose right or wrong. With that in mind there are times when a DA spirit may be obstinate, a prankster, bring on dark energies & feelings, but for the most part you’ll find it no different than being around any human companion.