Article snapshot taken from Wikipedia with creative commons attribution-sharealike license.
Give it a read and then ask your questions in the chat.
We can research this topic together.
Periorbital hyperpigmentation, also known as hereditary dark circles, is characterized by darker skin around the eyes caused by the presence of additional melanin. It is an extremely common hereditary human characteristic and is frequently found on individuals with dark skin. Periorbital hyperpigmentation is most prevalent within the 16–25 age group.