The reason you have brown stuff in your underwear is because you didn't clean yourself properly. Not wiping yourself can lead to an embarrassing stain on your underwear as a result of waste that was not cleaned up properly.
Poo
Often black dyes will turn brown when exposed to bleaching products. The underwear was probably bleached. OR You pooped your pants too often
This could be the beginning of your first period.
how am i suppose to know I'm not perverted
It means you will start you period soon.
pink unicorns with yellow stripes.
its probably skiddies :D hope dis helps
he throw away his underwear after one night
You might be starting your period in a couple of days.
yea!
A yellow brownish stain in a girl's underwear means that she will be starting her period ina couple of days so be prepared so that you won't end up with a bloody mess in your underwear and maybe on your pants.