Is this thing on Betta's tail a parasite or is it normal?

Look it up on Google images and try to see if you find anything that looks like what is going on, if you do, look up the thing (whatever it is) and see if it is dangerous or not. I dont think it is though, my Betta has a small little slender fin-piece that looks kind of clear, and he has been fine, and the same, for months.