1. this kind, the way they make love is so hot
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I like all those green, white (and red!) Martians from DC^^
And the black ones, you know, like Marvin and the Queen Tyranee in the Looney tunes XD

The Symbiote.

My favorite alien character? The list is too long.

Various, I'll tell you all the ones I can think of off the top of my head:

Lyja the lazerfist (Skrull)

Martian Manhunter (Martian, no REALLY!)

Fiz (Skrull)

Lockheed (Space Dragon... I THINK...)

Warlock (Technorganic Alien)

Beta Ray Bill (I can't remember what his people were called.)

Howard the Duck (Errr, Close enough right?)