God.  That second, lengthy vid is one of the most freaky and depressing -- and absolutely un-erotic -- things I have ever seen.
I think the most disturbing part is the comments section.  I felt compelled to post a comment myself, so now I'll probably get flamed for being a hater, but Jesus Christ.  Especially that last part, where she's got the plastic bag over her head.  I can just see lots of copycat asphyxiations from that one.
Have you seen 
this one?  She explains that she doesn't think she is very attractive (now 
there's a shock) and that she gets off on fantasies of being choked.  
All very scary and sad.