Ethan Rom.  We didn’t get a huge chance to see much of Ethan, until we started seeing him in some flashbacks in season three.  The first thing that I think of when I hear his name now, is his persistence.  If you remember, he altered the original plan of injecting Claire, and ended up kidnapping Charlie and Claire.  That tells me right there that he is persistent in what he does and doesn’t take no for an answer.  He seems like a kind person though, aside from a few moments.  I never really understood why you would send a surgeon to investigate matters going on, especially if he’s the only one they had.

Apparently, Ethan had some sort of obsession with Claire.  This is obvious, due to the fact that he probably kidnapped Claire and Charlie without any type of approval, but that’s simply speculation.  I believe that Ethan underestimated how clever the other survivors were, eventually leading to his death.  Ethan is also very convincing, as he assisted in talking Juliet into coming to the island to join the experiments.