After I've washed, my genitals are odor free but only for a few hours. I'm not sporty, so why is this?
I'd like to suggest that you try a little experiment...
Next time you get out of the shower, skip the deodorant/antiperspirant. Go about your daily life for several hours and then take a quick sniff of one of your underarms.
I can almost guarantee the results of this experiment. You'll likely find that your underarms smell a bit, even if you haven't been exercising or engaging in any strenuous activity. This is because even during normal activities, we all sweat a little. It's one of the ways our body can very carefully regulate its temperature. In fact, in reality your whole body has a bit of an odor once the soap or other personal care products you've used have worn off.
Just like your underarms, your genitals will sweat even during regular activities. You've also got various other bodily fluids going on down there as well. If you're female, you've got normal vaginal discharge (which is perfectly healthy) that will also have a scent that's added into the mix. Sweat and the other fluids your body produces mix to give you a general scent. And that's totally okay! We're humans, not flowers. So we're supposed to smell like people, not flowers or spring rain or whatever.
So, what can you do? The best thing to do is not to worry about this. As long as you're not having a foul odor or any other issues (foul smelling discharge, itching, burning, etc.), having a scent is totally normal. If you are having those issues, then it's time to head to your health care provider to make sure that you're in good physical health and that you don't have an infection going on. Using genital deodorants or douches or other harsh chemicals on your genitals is a bad idea. That's a really good way to get things really irritated or to give yourself an infection. So skip those things and stick with washing with a gentle soap (preferably fragrance-free and dye-free) and water when you normally bathe.
You may want to check out the following links for more information on infections and vaginal discharge: