Dexter tries to be there for Rita, he really does. But our favorite serial killer has problems feeling much of anything for anyone.
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Rita Bennett is pretty much as understanding as it gets. You'd have to be in order to date Dexter Morgan.
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Dexter Quotes

Deb: (excitedly) A baby? a motherfucking rolly-poly, chubby cheeked shit machine? Are you kidding me?
Dexter: I've never heard it described in quite those words before, but yeah.

Don't be sorry your darkness is gone. I'll carry if for you - always. I'll keep it with mine,

Dexter [to Lumen]