I don't know, but, I consider the Tywin incident justifiable in the context of the book.
I would have enough confidence in Tyrion's morality, in Westeros, that I would let him babysit my kids. Too bad he didn't have control of Joffrey earlier, or was Jon's mentor at an earlier age.
If I were a character in Westeros, I would definitely sleep with him. He sounds like he is funny, immoral in the right ways, conscientious in the right ways(Sansa) and active. Betraying him with his father, and humiliating him in a courtroom, where you helped convict him or murder, though, would not go well.
He has shown outstanding kindness, wit, creativity, courage, humour, trustworthiness, humility and loyalty, unless crossed beyond the pale. Even Catelyn was starting to trust him by the end. Wouldn't you like to have him as a friend, or ally, if you were not planning to heartlessly betray him?
This is also a world where murder is rather commonplace. Reading a book is not. A man who reads!