“So you came back, didn’t you?” said Harry urgently.
“People can come back, right? As ghosts. They don’t have to disappear completely.”
At the end of Chapter 38, Harry skips the Great Feast in order to spend his evening desperately searching the halls of Hogwarts for one of the school’s many resident ghosts. When Harry finally locates former Gryffindor member Nearly Headless Nick, Nick does not seem particularly surprised to see Harry. Often, students who have just dealt with the death of a close friend or family member seek out the spirits of Hogwarts, demanding more information on death and the afterlife. Harry is presently mourning the tragic death of his godfather, Sirius Black, and is incapable of accepting the idea that he may never be able to seek counsel from Sirius again. Harry is a bright and brave wizard, but his inability to accept the finality of Sirius’s end speaks volumes about the tenderness of his heart. As Dumbledore explains when he is telling Harry about Trelawney’s prophecy, it is the strength and conviction of Harry’s heart that sets him apart from the evil Lord Voldemort. While the strength of his heart causes Harry much pain, it is ultimately his greatest asset.
Nick responds to Harry’s inquiry by assuring Harry that Sirius is, indeed, gone. While some Wizards choose to continue walking the Earth, most decide to move on, and Nick quietly laments his own choice to remain at Hogwarts. Even after his encounter with Nearly Headless Nick, Harry is still not convinced that Sirius has left him forever. He runs into Luna Lovegood, who is the only person Harry doesn’t mind talking to about Sirius. Luna reveals to Harry that her mother died and explains that the voices she and Harry heard coming from behind the black curtain at the Ministry of Magic (the same curtain Sirius fell through to his death, and the same curtain Harry was inexplicably drawn to) are the voices of ghosts. Harry is skeptical but once again filled with hope that he might meet Sirius again.