Tactile Contact With Intimate Parts of a Human-Shaped Robot is Physiologically Arousing

Touching less accessible regions of the robot (e.g., buttocks and genitals) was more physiologically arousing than touching more accessible regions (e.g., hands and feet). No differences in physiological arousal were found when just pointing to those same
anatomical regions.”

Source: http://spectrum.ieee.org/automaton/robotics/humanoids/stanford-touching-nao-robot