to those of you of either sex who wear thongs or strings, doesn't the back side get in direct contact with your anus?

Why not spend a few bucks on a thong and find out?

because I don't want to waste money
- Then maybe buy a used one, or ask a friend to borrow
- They're worth it if you get swamp ass. You don't really notice it after like a week of wearing them.
  But, only get cotton or modal. The synthetic fabrics just hold moisture against your skin.
- it's only a waste if you don't like it...

i only notice them if i accidentally wedgie myself with them

oh and when i check myself out from a mirror, obviously

Is it true they play a G note when you fart?

Some people aren't afraid of their assholes.

no way, full backs feel like you're wearing a diaper and you still get wedgies anyways, so why not have a tinier more environmentally friendly wedgy and no panty lines?

if you're actually having the specific problem mentioned in the title, just size up. try plain ones instead of weird fancy ones.

Yes. It doesn't really rub, it sits still because it's tight against your body. Honestly you quickly forget you're wearing it after putting it on.

Yes. It’s sexy underwear, not comfortable underwear

they serve a functional purpose of not showing underwear lines when wearing tight and/or thin articles of clothing. so not always just sexy underwear

Why you all taking about your butts? I wear thongs in the summer. They're quick to slip on and pretty comfortable footwear.

"Thong" can mean a type of sandal, also known as flip-flops, but it's also the name of a type of underwear or swimsuit bottom that's basically a string in the back.
I grew up calling flip flops "thongs", but as I got older, people were almost exclusively using that term for the underwear, so I switched terms to avoid confusion.
https://en.wikipedia.org/wiki/Flip-flops https://en.wikipedia.org/wiki/Thong
If your thongs are touching your anus, you're wearing them wrong.

I wear them pretty often in nightlife. I had the worst wedgie from one last night. Usually you don't notice them but mine has thick straps (it's fetishwear, I'm a performer) so yeah...

I also wear a g-string underneath for safety

Guy here, I've worn a few in my time and it's a lot like wearing a new ring on your finger, at first you notice it constantly, you feel it between your fingers and you notice when it moves, but eventually you forget it's even there. Exact same experience with thongs. After the initial sensory experience wears off its as present in your mind as the underwear you're currently wearing. It doesn't move much between the cheeks, and I can't say I've ever explicitly felt it shading my asshole.

Personally I'm not a fan of them because they don't provide the two things I wear underwear for, padding between my thighs so they don't chafe, and decency if I manage to cut it rip my pants while working. If I don't need to worry about those I'll just go commando.

Wash your ass, dude.

You realize most people ONLY wipe when they poop, ...right?
- The bidet brigade has arrived 😂

I plug for a couple days at a time every once in a while, honestly you stop noticing the outside contact after a couple hours. Then you forget it's there for the most part until you move and it grinds against your prostate and you're like "oh right this is nice" and you start doing kegels and leaking in your cage

Cage?
- That's the first couple steps on a long and possibly terrifying road. Sometimes not knowing is more comfortable. You've been warned.
- Chastity cage! =D
  To help stop you jerking off. Getting super pent up and horny really really heightens anal for me, and it puts me in a fun subby headspace, even by myself
Pronoun, this is a Wendy's.
- Wen deez nutts? Around 8 pm
Lady, the question was "do thongs touch you butthole?"
Please tell whoever is holding the keys that a random on the internet said to let you cum, if not for your own sake then for the rest of ours.
- Hahahahahahaha

Isn't that the whole point? But no to the latter question. Your shoes rub your toes but you probably forget about it after a while. Ever wear sandals? There's comfy pairs and uncomfy pairs.