For my third proposal, i choose the Hassassin as a candidate to be a Pure Evil.
What's the work?
Angels & Demons is a 2000 thriller novel by Dan Brown. It's the first work featuring Robert Langdon, with The Da Vinci Code following Angels & Demons in 2003. The difference is the 2006 film adaptation of The Da Vinci Code is the first cinematic work featuring Langdon, and it was followed by Angels & Demons in 2009. In Angels & Demons, Langdon and Vittoria Vetra will have to solve the mystery behind the Illuminati and the Catholic religion.
Who's the candidate?
The Hassassin is the main antagonist of Angels & Demons. He's a freelance Muslim assassin of Arab descent associating the Illuminati. His film counterpart is rather named Assassin.
What has he done?
The Hassassin demanded Dr. Leonardo Vetra to get access his lab via password, but Dr. Vetra refused. So the Hassassin cut one of Dr. Vetra's eyes which turns out to be a key to access. He branded an Illuminati logo on Dr. Vetra and twisted his neck on 180 degrees. He then stole an antimatter, and he will use it to blow up the Vatican City (an action that would decimate many people in the process) as revenge on the Catholic Church. To get rewarded himself, he goes into the prostitution house and has sex with the prostitute in bondage, whom he considers to murder.
He kidnaps four Cardinals, and warns to the public that the Cardinals would be later killed each in four Churches. He brands an Earth symbol on the first Cardinal, and block his throat with the dirt, suffocating him to death. The Hassassin brands an Air symbol on the second Cardinal, and puncturs and asphyxiates his lungs. Still alive, the Cardinal, disguised as a tramp, fall and die publicly. This shock many viewers of his death.
The Hassassin brands a Fire symbol on the third Cardinal, set the fire above the Cardinal before leaving him burned alive. He then kills Olivetti in a way similar to Dr. Vetra. He drowns the fourth and final Cardinal in the fountain after kidnapping Dr. Vetra's daughter Vittoria Vetra at the Church of Illumination, and before battling Langdon.
After assuming Langdon drowned in the fountain (unbeknowst to the Hassassin, Langdon used the air hose to keep himself alive underwater), the Hassassin undresses. But as he's about to rape Vittoria, Langdon interrupts him and the pair engage in fight, in which the Hassassin overpowers Langdon. After Vittoria free herself by dislocating her shoulders thanks to her practice of yoga, she burns the back of the Hassassin with a torch to distract him. Langdon push him off the balcony onto the pile of cannonballs below, breaking his spinal cord.
Unlike his film counterpart who reluctantly drowned the fourth and final Cardinal in the fountain, and choosed to not kill Langdon or Vittoria as he claims he'd be "wasting bullets, since I wasn't paid to finish the both of you off", the Hassassin had tendency to kill and rape. His tragic background isn't revealed. He didn't even show remorse or intention of extremism.
Both versions of the character killed Olivetti and three kidnapped Cardinals in a gruesome manner and attempted to blow up the Vatican City, and the Hassassin twisted Dr. Vetra's neck after cutting one of his eyes and branding an Illuminati symbol on him, while the Assassin simply killed Father Silvano Bentivoglio by gouging out his eye instead. But also, the Hassassin also raped a prostitute and attempted to do so on Vittoria.
The character from the book is more heinous than his film counterpart with the total lack of qualms.