The Duff is very blunt. There was some swear and there is definitely some sex. A lot more than in typical YA books. 
 The Duff is very fast paced. I read this book in the wee hours of the morning during Read-a-Thon and despite my tiredness I could not go to bed until I finished this book. I just had to know what happened. 
 My only real complaint about The Duff is Bianca's relationship with her father. I mean seriously? It doesn't make any sense for her to behave this way. She was an enabler in a situation that did not need an enabler! 
 As much as I liked the book, I didn't like Bianca, but I didn't not like her either. Part of it was how she dealt with her father and the other part was how she treated her friends. I did feel sorry for her (her mother won't be winning any "mother of the year" awards) but she made a lot of choices that frustrated the hell out of me. 
 However, I loved Wesley. I know that sounds strange (he's a man-slut after all) but he is so likeable. He's everything you want in a guy, the man-slut issue set aside of course. He was caring, funny and mostly sweet. He has a crummy family too and I wish we could have saw a little bit more of it. 
 I liked Bianca's friends. At first I kind of felt like they were using her a bit, but that's really not the case as they genuinely care about her. Both Bianca's and Wesley's parents had some major issues. Everything was tied up pretty nicely at the end, but since I expected that it didn't really bother me.