User blog comment:Derax-Pagani/Fairy Tail Chapter 493 White Dragneel Review/@comment-4829046-20160711125947/@comment-25395791-20160716093742

Basically :P But I don't really think it applies to either Zeref or Irene. Namely, what characterises bipolar disorder are 2 basic moods that change constantly; depression and mania. The former I assume you know about, but mania is characterised by hyperactivity, fearfulness and feeling that one can do anything. So those 2 change constantly, which leads to my point, being that I don't think I saw Zeref being hyperactive, neither did I see Irene like that XD