"But then again Hollywood also throws out movies like Alien that pretty much show them to be quite demonic in their actions (possession)."
In Soviet Hollywood, Skynet possesses you. [/"Terminator Genisys"]. Oh, and just Hollywood? Crawl out from under that stone already, and think outside your own little 'universe':
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The Abh in the Japanese anime "Banner/Crest of the Stars" are essentially the Eldar & Tau in "WH40K". Only, there's one problem.
Not even all of Chaos, never mind the Necrons, Tyranids, least of all Orks, could last five seconds against their superior firepower & technology. Thus the Abh are worse than Demons.
...but that's not the half of it: The alien Abh were created by humanity, but became superior to their creators.
In Soviet Abh Empire, Lafiel possesses you.
Not bad, for the non-American Japanese, eh? I guess that's why Stan Lee didn't go to a North American stufio, but instead used 'BONES' in Japan to visualise his alien Skrugg-defeating "Heroman"
The 'Mimics' in "Edge of Tomorrow". A.k.a. "All You Need Is Kill": Japanese.
Tom Cruise Control going [i]beyond[/i] the 'Danger Zone' in "Yukikaze".
He'll need all his OT-VIII abilities to pilot that Super Sylph B-503: which also has an AI. 'Friendly Aliens', and what they do, you say? Must be jelly, because JAM doesn't shake like that. >:D