since you were asking about the extra spotting of melanin around some breasts i did a quick bit of research out of curiosity. by and large its just a natural thing extra melanin bleedover from areola, and there are some oil glands in that area that concentrate more melanin too. perfectly normal and natural and just means you're darker. though one should also be vigilant, as if any of the spots move from day to week, grow, or if they are only on one boob that could indicate it might be melanoma / cancer.... though one thing i saw was indicating simple friction from a too tight sports bra could also be a culprit there, so just be vigilant but dont freak out or jump to conclusions. thanks for a fascinating rabithole to look down, hope you found this interesting too.