Why does my boyfriend get brown stains in the front of his underwear?

embarrassing stains on underwear (info in comments) : r/CleaningTips

Should women be worried about their underwear getting discoloured in the middle?

Life saver': Blogger shares SIMPLE trick for removing stains in underwear

Brown discharge: What does it mean, and what should I do?

Guys, Why does my boyfriend have white stains on the outside of the back of his boxers only on the top of the waistband (pics)? - Sexuality

Should women be worried about their underwear getting discoloured in the middle?

About Those Mysterious Stains on Your Pants

Where do guys' dick and balls go when they sit on the toilet

Numero Homme's exclusive interview with Tom Ford : “Some guys are born with large, loose testicles. Others are born with small balls… ”

How To Get Underwear Stains Out Easily

I'm a female and I get brown stains on my underwear everyday. Also, it's always wet and leaves an odor. Do I need to be concerned about it? - Quora

Vaginal discharge bleaching underwear: Here's why