Look at how trustworthy and amiable he looks:

No one in King’s Landing likes or trusts Littlefinger: not Varys, not Pycelle, not Cersei, not Jaime, not Stannis, not Renly, not Tyrion, not Tywin, no one. He’s an incredibly obvious schemer who can’t stop monologuing in front of people he’s trying to scheme against or reminding people he’s betrayed that he’s betrayed them. He should try to hide it, but his compulsive need to prove he’s smarter than everyone else won’t let him.
Littlefinger gets away with it because A. most people don’t see him as a threat because he’s got no lands and no armies, B. he’s made himself indispensible as the only person who understands the royal finances, and C. he’s pretty good at hiding his actions.