I would be pleased to answer your question .
There could be a source of bites on your legs which many range from termites to fleas to bed bugs. The other cause for such a recurrent pus filled breakout which leaves behind scarring might be recurrent folliculitis
You will need to take an oral antibiotic for the same and topical applications of a steroid
and antibiotic combination would be more helpful .
Please do show the Dermatologist
to confirm the above diagnosis
Thanks and Take care