Appearance and Personality Edit
Petyr Baelish is a thin and rather small man with dark hair threaded with grey, a sharp beard (and sharp features in general) and grey-green eyes that are apparently cold enough that they don't laugh when his mouth does. He always has the scent of mint on his breath. He tends to dress in black and his personal sigil is a silver mockingbird, as opposed to the Titan of Braavos that emblazons his family's flag.
Highly intelligent and ambitious, Petyr is well known for being extremely cunning and Machiavellian, and has been so his entire life. On account of the fact that he was born to an incredibly lowly house in the Vale, his father was a foreigner and he has a track record with several great lords (namely the Starks, Tullys and Lannisters), nobody truly trusts him, but too many people make the mistake of eventually bowing to his silver tongue. Eddard Stark was among these people, even though Petyr cheerfully admitted that trusting him was a mistake. Even though Petyr comes from a low background, he is a better politician, schemer and mastermind than almost any other lord in Westeros - the possible exceptions include Varys and Tywin Lannister, but Petyr matches them with his serene ruthlessness and unpredictability.
Whether or not Petyr is an inherently evil man is debatable to say the least: he admits that he has always loved Catelyn Stark, and fought an almost fatal duel against Brandon Stark for her hand. When Catelyn was killed by the Freys in the Red Wedding, Petyr vengefully murdered Joffrey Baratheon at his own wedding, scheming with the fearsome Olenna Tyrell to do so. He is actually rather fearless, personally confronting the Lords Declarant whom he knew were dangerous and intent on destroying him, and playing perilous games with powerful men and women, over whom he is completely confident in his advantage. However, even these factors lead to weaknesses: Petyr may have loved Cat, but this love changed perversely when he kissed Sansa Stark and started being overtly intimate with her (which was publicly excused with the shared lie that he was her father, while she hid in the Vale).
Petyr has no qualms about breaking sacred laws such as that of marriage, since he murdered Lysa Arryn when she threatened to expose the shared plan of murdering Jon Arryn. Petyr appears not to notice that his schemes of murder and corruption, betraying and applying to the deaths of Jon Arryn and Eddard Stark, have led almost inevitably to the death of the woman he loved, and the obliteration of her family. His catharsis from Catelyn's murder was simply to murder Joffrey, which resulted in even further dismay from the killings that followed the Purple Wedding. Therefore, it is clear that Petyr, for all his motivations, is a dangerous man to cross.
He grew up poor in Riverrun with Catelyn Stark and Lysa Arryn, and fell in love with Catelyn there, while Lysa fell in love with him. When Catelyn was engaged to Brandon Stark, Petyr challenged him to a duel for her hand. Catelyn gave Brandon her favor and shunned Petyr, and he lost the duel. Petyr left Riverrun in shame and later became Master of Coin for Robert Baratheon and the Iron Throne.
He is well-known for playing false and having his own best interests in mind; when Eddard Stark came to King's Landing to be Robert's Hand, he sought help from Littlefinger. After sneaking Catelyn into King's Landing and then smuggling her back out, Petyr turned around and betrayed Ned to Cersei Lannister (though he did warn Ned not to trust him.) Petyr later reveals to Tyrion Lannister that he took Catelyn's and Lysa's maidenhood, and in A Storm of Swords, he goes to the Vale to convince Lysa Arryn to join the side of the Iron Throne in the War of the Five Kings. Instead of winning Lysa to his cause, he stays to court her (as she has never fallen out of love with him). Later, he spirits Sansa Stark away from King's Landing and the Lannisters to bring her to the Vale. Petyr claims that Sansa is his bastard daughter "Alayne" to protect her from those who would harm her. He has always loved Catelyn but she is dead now and he starts falling in love with her beautiful daughter Sansa who is "more beautiful than she ever was" says Petyr comparing her with her mother.and later kisses her. When Lysa finds out, she threatens to kill Sansa, but Littlefinger has her killed It is in this scene that Sansa learns that Littlefinger convinced Lysa to kill her husband Jon Arryn.