Rape fantasy is very common in the Japanese
culture. It is, perhaps, the single most common fantasy for Japanese males, and not at all uncommon among males in general. It is essentially a form of domination fantasy
IMPORTANT: Be careful not to confuse rape fantasy with an actual desire to rape! It is a fantasy... not even a wish.
Rape fantasy, from a dominant viewpoint, is a fantasy about taking someone else and bending them to your will, usually to the point of breaking their will, turning them into a willing participant.
I can't speak from a submissive's viewpoint, unfortunately... perhaps someone else can elaborate on how those fantasies run.