saddest part of elfen lied?

The saddest part for me was when we first saw nana at the lab, chained up, bloody, that almost made me stop watching. To see her so desperate to please her "papa" was terrible

Really, read manga, it is worth it. I have never read manga before, Elfen Lied was my first manga and the ending of manga series was so tragic, sad, but also epic; I literally fell in love with it. After reading it, I felt like my best friend just died ;( I have seen all of anime episodes, but in manga, there are some things, they didnt put in anime. This series made me so sad and emotionlly crushed, that it blocked me from reading any other manga comics. Lynn Okamoto really made a masterpiece.