She had a reason to lie to Voldemort. If Draco is alive, she needs to get into the school to see him and protect him, and helping Harry feign death was the easiest way to do that. But if Draco was already dead, she wouldn't have bothered. She would have told Voldemort immediately that Harry was alive.
When Voldemort asked her to check if Harry was dead and she realised he was, in fact, still breathing, Narcissa seized her opportunity. Harry revealed that Draco was still very much alive, and she lied to her master in order to get closer to him.
Although never officially a Death Eater herself, Narcissa believed in the importance of blood purity and supported her husband in following Lord Voldemort during the First and Second Wizarding Wars. This changed, however, when her husband was incarcerated in Azkaban and her son's life was put in jeopardy by Voldemort.
Draco Malfoy was allowed to continue attending Hogwarts after his father Lucius was arrested for being a Death Eater at the end of Order of the Phoenix for the same reason why the children of convicted felons in our own world aren't barred from attending schools.
According to Rowling, Malfoy originally makes an effort to be Harry's friend because "it will be cool to turn up at the school being Harry Potter's friend, because Harry is so famous." However, Harry did not want Malfoy as a friend because he "has been so rude about Rubeus Hagrid and about Ron, who Harry likes so much" ...
“Harry was constantly crushing on Draco. He just couldn't hide it.” In the books and movies, Harry and Draco are constantly at each other's throats, given that Draco's parents are Voldemort supporters and the evil wizard killed Harry's parents.
Specifically, Draco was jealous of Harry. It was easy to miss because Draco didn't often show his emotions, modelling himself on his cold, confident, calculating father, but J.K. Rowling has confirmed that a lot of his enmity towards Harry stemmed from envy.
Despite being a valued Death Eater in the days before Voldemort fell following his attack on baby Harry, Lucius stumbled out of favor with the Dark Lord when he squandered Riddle's diary (secretly a horcrux) in Chamber of Secrets and failed to obtain the prophecy in Order of the Phoenix.
Peter Pettigrew (a.k.a. Wormtail) is the only Death Eater known to have been in a House other than Slytherin (Gryffindor) while at Hogwarts. There, he was a close friend of Sirius Black, James Potter, and Remus Lupin, although he was the least intelligent and least talented of the group.
Draco had several reasons for lying to Bellatrix, including the fact that he was never a bad person. Moreover, he no longer found working for the Dark Lord appealing and hated how Voldemort treated his family. He did not intend to harm anyone and believed Harry was the only person capable of defeating Voldemort.
Voldemort intentionally made six Horcruxes, but when he used Avada Kedavra on Harry, he unintentionally created a seventh Horcrux. Instead of dying, Lily's love for Harry created a counter 'curse' known as Sacrificial Protection and saved Harry.
In fact, Lucius' own support to Voldemort is revealed to come only under some form of duress, which is likely Narcissa's Veela Allure. When Lucius turns on Voldemort due to the reveal of his Horcruxes, Narcissa divorces him, taking 75% of Malfoy's wealth with her.
Harry held Narcissa in contempt due to his rivalry with her son and hatred of her husband. In the same respect, Narcissa held Harry and his friends in disdain and contempt: especially Hermione Granger, as she was Muggle-born, and Ron Weasley, as he was a blood traitor.
Draco says she suffers from a “blood malediction,” which ultimately ends up killing her the summer before Scorpius's third year. While it isn't clear that Astoria's and Nagini's conditions are the same, Draco's description of her illness seems to match up with new information from Rowling's tweets.
Why did Narcissa Malfoy lie to Voldemort and say Harry Potter was dead when she knew he wasn't? At this point in the Battle, Narcissa Malfoy had been completely separated from her son. She didn't know if he was alive or dead. Being the mother she is, first and foremost, she no longer cared if Voldemort won or lost.
“Is Draco alive? Is he in the castle?” The whisper was barely audible; her lips were an inch from his ear, her head bent so low that her long hair shielded his face from the onlookers.
Worst: Lucius Malfoy
Lucius Malfoy is pretty clearly a bad person, but he's a perfect example of how banal cruelty and evilness can be. Lucius likes to control, humiliate, and cause people pain, but he's also too weak and self-absorbed to really become one of the evil "greats," so to speak.
In the world of Harry Potter as we know it, there are no recorded instances of a person who was sorted into Hufflepuff ever becoming a Death Eater, or any other kind of Dark Wizard for that matter.
1. Voldemort. Tom Riddle took the core qualities of Slytherin to new heights, as he became arguably the most powerful dark wizard of all time. He learned how to split his soul and create numerous Horcruxes, thereby making himself immortal as long as the Horcruxes existed.
Voldemort had waged psychological warfare on the Malfoys, and knowing that he held total power over them- he fully took advantage of his situation. He wielded his power to the point that they no longer wanted to follow him- but they were in too deep.
Isaacs brings up Lucius' disheveled appearance in Deathly Hallows, raising the possibility that the Malfoy patriarch had begun drinking too much. The way Isaacs saw it, Lucius was in a no-win situation. Given everything he'd done, the man no longer had a place on either side of the war.
In the battle that ensued, the prophecy was destroyed, and Lucius and his comrades were imprisoned in Azkaban in 1996. Although Voldemort broke them out of prison in 1997, he was displeased with Lucius for his failures and treated the Malfoys with much disdain and abuse.
The pressure of being in the Slytherin house and being the son of a death eater, all that stuff. ... Because Draco could not face what he had to do to save himself and his beloved parents from death. He realized more and more how much he dreaded to have blood on his hands.
Based on Harry Potter lore, and an article by The Healthy Journal, Draco's signature spell is a N.E.W.T standard spell, The Protean Charm.
Draco was torn between loyalty to his family, fear of Voldemort and worry for his former classmates.