What should i do if one of my site have LOT of loq quality internal links? I mean like this one: http://xxx.xx/sex-girl-photo/74430 and inside it just a photo and some more links to related photos? Should i allow it to index or not?
If they are internal you may let them on indexing it. Of course if the site has lot's of low quality internal links then you should not allow it because it may decrease your ranking quite a lot.
If you wanna remove the low quality backlinks then just submit your website into Google disavow via Google Webmaster Tool, it will take approximately 2 to 3 weeks and the low quality as well as Spam backlinks are removed or deindexed by Google.