The aspects of this fetish that are most appreciated by members of the ASFR community are greatly varied. For some, things like robotic appearance, motion, or sound are important for arousal. For others, these are not, and a completely life-like android that appears to be human is desired. This holds true for other aspects, such as sentience or self-awareness. The ability of the android to remove parts of its skin or other bodily appendages in order to reveal its circuitry is quite pleasing to some, but distasteful to others. There is a further divide between those who prefer an android to appear human-like and those who would prefer a more mechanical looking robot, i.e. with a metallic surface.
Damn, i have to remember the name of this artist. His works are all about robosex.
(UPD: http://hajimesorayama.com/. His name is Sorayama. And he calls this Robot Pin Up.)
Connected with Transformation fetish - a context of sexual fetishism in which a person becomes sexually aroused by descriptions or depictions of transformations, usually the transformations of people into other beings or objects; and Doll fetishism - a sexual fetish in which an individual is attracted to dolls and doll like objects such as figurines. The attraction may include the desire for actual sexual contact with a doll, a fantasy of a sexual encounter with an animate or inanimate doll, encounters between dolls themselves, or sexual pleasure gained from thoughts of being transformed or transforming another into a doll.