According to TBoneTheOriginal, his condiditon is the result of pilonidal cysts:
I've had multiple surgeries on it, and instead of the usual procedure which involves letting it heal, mine was so bad that a plastic surgeon had to close it up. But they keep coming back, and it'll probably just get worse as I age.
To answer a couple questions: My butthole looks the same as anyone else's! The wound just goes very close to it. Trust me, you don't want to see it. Second, I poop like anyone else. Just gotta be careful with wiping so I don't get feces in the wound. But it isn't hard after having to do it for 8 years now.
Also, for the record, TBoneTheOriginal's lack of a buttcrack has not altered the sound of his farts. They're still "perfect pitch," in his words. All eager Redditors—along with the rest of the world—have now been enlightened.