Kilgrave (Jessica Jones)
Kilgrave, played by David Tennant, is the antagonist of the Marvel Netflix series, Jessica Jones. He possesses the ability to convince an individual that they want to do what he tells them. He uses this power to steal and rape, having a particular interest in the titular Jessica Jones.
Sympathetic villains are usually sympathetic in ways where the viewer can understand their actions due to their cause. Mr. Freeze from Batman and Magneto from X-Men are both iconic villains whose actions are somewhat justified by what they are trying to achieve. Kilgrave, however, is a twisted narcissistic individual who, even at the beginning of the series, has committed so many irredeemable acts that one could never imagine feeling anything but contempt for him. However, as the series goes on and Kilgrave develops, you see what made him this way. Tested on from a young age, Kilgrave developed his powers of manipulation. The power of influence was so strong and so constant, that he'd never known life without them. This caused him to develop a sick sense of entitlement and resentment. His broken psyche fostered unhealthy feelings about relationships, and as he became more interested in Jessica, and in turn forced her to become more "interested" in him, he truly believed that they were mutually falling in love. This instills scenes in which Jessica insults him or denies him with undertone of pity. Due to Tennant's performance, you can see true pain and even self-hatred in his response: a simple pitiable swallow and a melancholy look in his eyes. Kilgrave's motives and methods are both disgustingly deplorable, but the powers he never asked for enable the viewer to feel a split-second of pity and empathy, before chastising themselves for caring for one of the most appalling villains of all time.