Broadwaybound, Benny most certainly *is* the villain of RENT. Just because he's a rounded, well-written character who shows a bit of heart doesn't mean he isn't the antagonist of the story. He's the landlord threatening eviction if rent isn't payed! The only other villain in RENT is the AIDS virus, and that's not a character.
Besides, while Benny tries to help Mimi at the end, he also cheats on Alison with Mimi, illustrating his lack of true morality. He threatens to evict his friends, only offering them a reprieve if they stop Maureen's protest, which will be an embarrassment to Benny in front of Mr. Gray. Benny is evil without being inhuman.
And to all those who say Thenardier is the true villain of Les Miserables: while he is a villainous character, Javert is the villain to Valjean's "hero." Javert is in direct opposition to Valjean, the protagonist. And while he is following the law, it still holds true that he is the force working against our story's hero, thereby making him the story's villain.
Besides, he shows his lack of morality during the battle: he tries to sabotage the rebellion! "They intend to starve us out before they start a proper fight - concentrate their force: hit us from the right." Gavroche proves he is lying, that he is a spy from the other side. He even says, "I will join these people's heros, I will follow where they go, I will learn their little secrets, I will know the things they know," that he will "nip it in the bud" and refers to the rebels as "schoolboys" who will "wet themselves with blood." He most certainly is a villainous character!
"It's not for sissies, contrary to popular belief." - Tommy Tune, on musical theatre.
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