The real-but-unofficial name is Another Fucking Driver. I see a lot of comments online of people saying they used to work at Microsoft or heard from a friend that works there explaining how it got this name, but I 100% remember watching a Microsoft Build conference (maybe ~10 years ago?) where the person who wrote it said on stage that he really did call it that, but they had to name it Auxiliary Function Driver for obvious reasons.
Sadly I can't find that talk anywhere on the internet, but it definitely happened.