Gaap is a demon that visits Nida in the episode ‘Demon 79’ in Black Mirror season 6. The character is played by Paapa Essiedu.
Gaap is a demon who is up for initiation and after Nida marks his amulet with her blood. He gets her permission to present himself and shows up in his original demon form.
To make her more comfortable, he takes on the form of someone she enjoys and ends up as Bobby Farrell of Boney M. Gaap tells Nida that she needs to make 3 human sacrifices in 3 days or else the apocalypse will come.
He mentions that this is his assignment as well so if he doesn’t succeed in making Nida do the sacrifices, he will be cast out in endless oblivion.
A guiding hand
Gaap can show Nida the future and tell her a person’s worst acts so that Nida’s decision to kill them becomes easier. He pushes her to make the first kill after running into a man that molests his daughter.
Then he talks her through the aftermath and keeps her steady and she slowly gets used to the situation that she’s in. After making a double kill on the second night, Gaap tells Nida that she’s done but when the talisman isn’t updated, he makes a call to Hell to find out what the deal is.
That call reveals that his full title is Gaap of Misophaes and that he was bound to the talisman in 1926. Misophaes is a class of demons found mostly in the lowest portion of Hell.
Gaap does ask Nida to choose someone other than Michael Smart because he’s beneficial to Hell and when she doesn’t listen to him, he goes away.
He only shows up at the end when she’s in the interrogation room right after midnight. He tells her that he’s being expelled because he failed and then asks her if she would like to join him for the company since her world is doomed as well.