What's the smallest fandom you are a part of?

So I'm sure most of us here are part of multiple fandoms of varying sizes. Harry Potter and ASOIAF are probably the two biggest fandoms that I regularly participate in but I am a part of a few smaller fandoms.

Mobuseka (The World Of Otome Games Is Tough For Mobs) is one of my favourite fandoms but it probably has less than 200 combined fanfics on all platforms combined.

Another is the Hierarchy series/The Will Of The Many which is a fantasy series with only one book out so far which came out back in 2023 with book 2 coming out in November so it literally only has 12 fics on AO3.