Pigmentation on Legs
It is very hard from the photos to discern what is going on, but it appears as if you have what is called "post inflammatory hyperpigmentation." This is pigment that develops after a trauma or irritation, likely due to your previous history of bites or cuts on your legs. You will need to see a cosmetic dermatologist who has training in lasers. You will likely need a combination of topical treatments with bleaching, vitamin A and C, and sunscreen. There are options such as microdermabrasion (silkpeel), chemical peels, or lasers that may be useful. But sometimes no treatments are affective for this, and you need a formal evaluation to determine what may or may not be helpful. I wish you the best of luck, Dr. Emer.