Perversion

[Sarah]

The act of perverting something.
A tweak, change, or adjustment of an otherwise true or accurate person, place, thing, or idea, to the point of making the person, place, thing, or idea no longer true or accurate.

[Sarah]

sexual behaviour that is considered strange and unpleasant by most people:

[Lanell]

The alteration of something from its original course, meaning, or state to a distortion or corruption of what was first intended.