Females:
There could be a number of reasons such as...
You're not practicing good hygiene
You aren't washing your underwear (wearing it for a long time)
You could have a STI/STD
Yeast Infection
You could be on your menstrual cycle
Keep in mind all female private area's naturally have odors.
Males:
There could be a number of reasons such as...
You're not practicing good hygiene
Moisture build up under foreskin
UTI
Yeast Infection
STI/STD
Wearing tight underwear (allows sweat and bacteria to fester)
Long Pubic hair (can trap moisture and bacteria)
Males also naturally have odors contributed to sweating in the groin.
