First of all there is the cover. It is always printed on much better paper than the rest of the book, and of course has much larger print and the colors stand out more glaringly and forcefully. The title also counts for a lot. The scene depicted on the cover is usually violent. It is intended to catch the child's attention and whet his appetite.
For example, in a comic-book reprint of a newspaper comic strip—the cover shows a scene which does not occur at all in the strip. In transforming this comic strip, intended chiefly for adults, to a comic book for children, this scene is added: A young woman with prominent breasts and nude legs is lying on a cot. Her lips are rouged, her hair falls loosely in masses over her bare shoulders and her face has a coquettish expression. This is supposed to be the scene of a surgical operation! There are two white-gowned and white-capped men beside her, one about to put a chloroform mask over her face, the other holding scissors in his right hand and in his left a knife whose sharp blade is surrounded with a yellow zigzag halo (used in comic books as a rule to designate the effects of cutting or shooting). The whole scene has nothing to do with medicine and is unmistakably sadistic.