Sheet Metal Girl

Great song. Great band. Ohh yeahhh.

insest=bad. someones sister is apparently a little to attracted to her brother "parting her silver thighs and making love obsolete".

My interpretation is a bit different, but doesn't explain the use of the word 'sister.'

It seems to be about a android or robotic girl used as a sex object, and thus "making 'love' obsolete." The ultimate electric vagina!

having sex with some sort of robot

These guys are so psychopathic...but I suppose that's what it takes to make such blindingly heavy music.

Awesome song

I can see three possible interpretations:

1. As everyone has said, he's speaking of a robot designed to fulfill one's sexual needs. If this is the case, I have a theory regarding the usage of the word 'sister'. He could be severely emotionally stunted (which would make going to such measures understandable). He's a distant man, seeing in an android his emotional equal.

2. He's in a loveless relationship with a woman that he cares about, but the affection he offers isn't reciprocated. She's physically human, but she's so profoundly empty and absent of emotion that interacting with her feels like interacting with a robot. This, however, does make the sister bit confusing. Maybe she feels less like a lover, and more like a relative. There's love there, but in physical matters (sex) there's absolutely none.

3. They're in a loveless, physical relationship, and he's ok with that. He's cold, but nothing compared to her, and he admires her personality. "My bionic sister teaches me inhumanity" - he wishes to attain this level of indifference from his comrade, his sister in utter nihilism.