When a man takes a decapitated head, mounts it neck first on his penis and then spins it around ala Linda Blair in the Exorcist, that's rotoscoping. As a hobby, the risks probably don't outweigh the rewards.
"What a bunch of bullshit that I got arrested for rotoscoping. I found the head in a vacant lot. Geez, it's not like I'm the one who killed her."