Joyce wants to know: How realistic is Italo's reaction to Iachimo's clear mental problem? Am I missing something? Are there possibilities for Italo that I haven't explored? I do wish to keep him the "sane" one of the two, whatever that may be. These brothers originally started out as antagonists. Do you have any suggestions on how to keep Italo a "villain" and not have him become a redeemed bad guy by the end?
Family members of people who have a severe mental disorder are often put in this exact same position. Italo isn't doing anything out of the ordinary trying to protect his brother or keep him alive, especially given the request of his father. It's not even unusual that Italo is the younger brother, performing the "duties" of the older brother, such as protection and care taking.
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Since you're not wanting Italo to be redeemed by the end of the book, I'd at least consider having him work through this issue with Iachimo. Italo standing by and letting his co-captain do these things does reflect badly upon him and Iachimo, perhaps even more so, since Italo doesn't have the mental problems Iachimo does.
To keep him a villain...I've got a great scenario in my head. Let's say his brother's sadistic tendencies get worse, self-destructive to the nth degree. If Italo believed that it would be (or even not be) in Iachimo's best interests to go ahead and give up his life (either because Iachimo is so miserable or he's making Italo's life miserable), then if Italo were to sacrifice Iachimo for the greater good (or Italo's own greater good), this would be a bittersweet, anti-heroic measure.
Wow. That was a convoluted sentence. I just reread it, but it says exactly what was in my mind. I hope it translates!
Hope that this helps out. I welcome any further questions below.
Let's Analyze: What examples from fiction (movies or books) can you think of where a villain turns on someone close to him--maybe even someone he protected--to further his own agenda or to put the other person out of their misery?