Gettingit.com: Dressing Up Dick
In days of yore, Japanese men of the upper classes would wrap their penises in layers of cloth before going to bed with their wives and mistresses. This was because the more complex a man could make his wrapping, the longer his wife might take to unwrap that “gift” — thereby prolonging the pleasure. Out of this subtle and creative foreplay, kokigami, the art of paper penis costumes, was born.

And, for more on the topic check out the … “Phobia of the week: Ithyphallophobia — fear of seeing, thinking about or having an erect penis-
When a Penis is too Big to See.”