| Re: boyfriend's penis
First, the penis is always made of two different kinds of skin. It's normal, regular skin on the shaft, but the glans and inner foreskin are mucosa rather than regular skin. The mucosa is the pinker (or purple-ish) skin around the glans and the skin of the glans.
A stark color difference is a pretty normal appearance of a penis after circumcision. The foreskin has a smooth transition from the skin color of the outside to the pink color of the inner mucosa, but after circumcision the color change is often really noticeable with a scar separating the one color from the other.
That's another thing, depending on what circumcision method was used, there can be a more or less visible scar. For instance, the popular Gomco clamp leaves a ring of dark skin (that was the skin crushed in the clamp). As far as I know all the clamp methods leave these scars from the crushing action of the clamp.
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