in the crotch of girls
jeans that pops up when they sit down. The resulting image
looks as if the girl
has a small but erect penis in their jeans.
shows up because
of the jeans remains somewhat stiff while the denim wrinkles tightly when the fabric is compressed from sitting.
The same fold
appears on men's jeans as well, however it is common to see humps in the crotch region of a male. Special note is taken when it happens to a female.