Probably serial killer if you consider he most likely killed his older brother and cars of missing people were in his possession at one time . But Ed Gein was different from most serial killers because even after his crimes were revealed people still said he was a nice helpful man though he was an oddball.
His activity of grave robbing and using the body parts for bowls, furniture and articles of wearable items with his profound hoarding made him somewhat unique.
It seems as if even he killed more victims ,and the partial remains were used for the same purposes as the graveyard remains coupled with how badly he hoarded his house out they likely could have gone unnoticed or confused with the graveyard remains. This happened in the 50s when forensic s were scarce to non existent in remote locations so I am not so confident that every body part found was properly identified as belonging to his two murder victims or the remains he stole from graves.
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