Yap, you’re right, this is anal lube and you can guess but I think you already know why it is on that fresh asshole.
When it’s everythink prepared and hole juicy butthole is covered by viscous lubricant it’s ready to put a huge cock in it. It looks so sexy that I could stick my dick in that lube covered tight asshole at any time and take off that babes anal virginity forever ;). You just look how that sweet pussy popped out when narrow asshole was filled by massive dick! It looks amazing.
You can watch it from way closer, just visit Teach My Ass website and enjoy.