A photograph of a teacher on a school textbook was taken from a pornographic movie, reports Rocket News 24, leading to trouble for its Thailand-based publisher.

Holding a "Mathematics" folder and embedded in an otherwise normal textbook composition featuring 3D charts, a happy student and a male teacher writing out equations, nothing about the image suggests anything untoward. But the frame is clearly lifted from a scene in another movie, as depicted (safely for work) below.

The actress is Mana Aoki, and the photo was previously seen in promotional material for her movie "Costume Play Working Girl." The textbook has been reissued with a new cover.