Tyrion's book counterpart is every bit as ruthless, greedy, lustful, and power-hungry as the other members of House Lannister. He maintains a prodigious degree of cunning, revels in exerting power over others, has a massive ego, and is capable of committing acts of great cruelty to those that cross him. His Pet the Dog moments are reserved for those close to him and fellow outcasts, for whom he has a soft spot due to his status as a dwarf.
While Tyrion certainly has Adaptational Heroism in the show, I don't think his personality is all that different. He's a smart, vain, cocky, wisecracking, resentful Sad Clown in both versions.
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While Tyrion certainly has Adaptational Heroism in the show, I don't think his personality is all that different. He's a smart, vain, cocky, wisecracking, resentful Sad Clown in both versions.