It is walking on you. And then what? It goes away. Spiders don't bite you unless you piss them off, like hurting them or touching their webs.
The feeling freaks me out >. < I don't actively hunt them... I scream really loudly, my dad comes and if possible, gets the spider and takes it outside. It's bad luck to kill spiders in my culture o.o
Get used to it. :: ) It's not bad. Besides, spiders rarely walk on you. They mind their own business, they know well enough that you are a titan compared to them.
I love spiders actually. I used to have a pet spider until I was told to get rid of it... which made me emotional but whatever. xD