I am in a same sex relationship and I want to adopt my girlfriends son but I don't know what the laws are in West Virginia.

After you and her marry, and if the child's bio father will sign over his rights to allow the adoption, yes you can.

*** edit, did not see the same sex relationship first read,

West Virginia doesn't have a law that explicitly allows same sex couple to step-parent adopt, however, they have allowed second parent adoption. Thisis a good link. (The info regarding W.Virginia is on page 4). I do think you need a lawyer though.

Most attorneys offer a free initial consult.

In your situation I wouldn't even begin this process without an attorney. So shop around for one.