Yeah...

RE: Book DM's long-term popularity:

My very short and useless answer is because the DM chapter in QotD is such a banger! As are the rest of their scenes in that book.

The longer answer of why I love book DM is something Assad has touched on in several interviews: Armand has spent his entire life (or at least the years of it he can remember) trying to be what (he thinks) people want him to be.

He was trafficked, groomed and very violently indoctrinated into a cult, and never really 'deprogrammed' out of the ideas that instilled in him. He's never been able to be himself or even to explore what being himself means. Until he's with Daniel.

The DM chapter is very long and covers the entire arc of their relationship from their first meeting to Armand turning him 12 years later, when they have been lovers for years.

DM is very unhealthy in the books. Armand tells Daniel to start running and that he won't kill him as long as Daniel stays interesting to him, and chases him around the world for years. At first Daniel is terrified, but their interactions change over time. They talk, they argue, Armand wakes Daniel up in the middle of the night to demonstrate the miracle of the long-distance phone call to him, bails Daniel out of jail by pretending to be a lawyer and warns him when there's a fire in his hotel. And Daniel starts looking forward to seeing him and missing him when he stays away too long.

Even after Armand confesses that he'll never kill Daniel because he's grown to love him (and they immediately decide that means they're going steady now), their relationship is very unhinged. They're super codependent, Daniel is addicted to Armand’s blood and constantly demands that Armand makes him a vampire (because Daniel learned precisely nothing from interviewing Louis and can't understand how horrible being a vampire is), and Armand often disregards the physical restrictions of Daniel’s human body in terms of him needing rest. Daniel regularly storms out of their shared home because he thinks Armand doesn’t love him enough to give him the Dark Gift when it is in fact love that keeps Armand from giving it to him (Nickistat parallels, anyone?). This is their big conflict/fatal disconnect once they get together. But Daniel can't live without Armand and always ends up begging Armand to come take him home while cursing him for ruining him for a normal life. And Armand does come to take him home, but only after Daniel can't take it anymore and asks him to (dare I say show!Gabristat parallels?).

They are so super star-crossed and Daniel’s mortal lifespan constantly hangs over them like Damocles' sword. (Insert dreamy sigh.)

BUT it's also romantic, and incredibly freeing for Armand.

Armand is disconnected from humanity and doesn't really care if he lives or dies before he meets Daniel (he's been alone for a while by that time, Louis already having left him before the interview took place). Daniel and how clearly Daniel is a child of the times he was born in fascinate Armand. He literally tells Daniel that Daniel is going to teach him about the modern world and human life, and he does (though it's moreso Armand dragging Daniel to every place and activity under the sun).

They go on cute little dates and do domestic and goofy shit together. They take night classes, explore the jungle, debate philosophy, go to plays and art shows and parties, sponsor a dancer's education, watch the same two movies over and over, and Armand tries out a bazillion hobbies like microwaving rats and roaches, concocting unholy smoothies in a blender, interviewing random people on the street and filling a whole apartment with floppy disks full of 'secret writings'. Every weird thing that you assumed was fanon came directly from Anne Rice's typewriter.

With Daniel, Armand gets to do whatever mundane thing he wants and not be judged for it (though Daniel does grumble and grouse like a put-upon sitcom husband). Daniel is also a total monsterfucker who loves Armand 'not in spite of the fact that Armand is a monster but because of it' (literal book quote). For the first time ever, Armand is seen, he is loved not for who he's trying to be but for who he is (despite Daniel wanting something from him that Armand can't bring himself to give him). Being with Daniel brings Armand back to life. It makes him care.

By the end of the DM chapter, the vampocalypse has already started and Armand is terrified of it, because he doesn't feel like he can protect Daniel from it. Daniel is also actively dying from consuming too much drugs and not enough food and Armand is *shocked* by how much he cares. By how much he doesn’t want Daniel to die and how he can’t see himself going on without him.

So he (selfishly, in his mind) breaks his vow and brings Daniel 'into Hell' with him. ("We'll be in hell together after all".)

Anne initially intended for Armand to join Akasha and go fully evil, but then she wrote DM and with it a reason for Armand to want to save the world instead.

Ship of all time for real. Fucked-up gothic romance for the ages.

(I can't find the 'Teletubby falling over' gif on Tumblr so you'll have to imagine it at this point on my TED talk.)

RE: show DM and aging Daniel up:

I literally gasped out loud when the IWTV pilot revealed that the reason why they aged Daniel up was because this was a second interview. It's so brilliant. Not just in terms of framing the theme of memory being a monster/dealing with Anne's complete 180 on how Lestat is portrayed in the TVL book vs in the IWTV book, but (I realised after the Armand reveal) it also makes DM so much juicier.

In the book, their relationship and the ways in which Daniel copes with it are literally killing him. And Armand breaks his vow of never making a vampire by 'dooming' Daniel into immortality because he cannot bear the thought of having to face eternity without him.

The fan theory that was accepted by 98% of the DM fandom immediately after the Armand reveal (and which I believe will be what did happen in the show) is that past DM happened but Daniel doesn’t remember. Instead of turning Daniel because their relationship was killing him, Armand made the decision to remove himself from Daniel’s life completely to save him. He let Daniel go, so Daniel would have a chance to live a normal life. (Of course that didn't happen, which makes it even juicier still.)

Except now that Daniel is old and sick and close to dying of natural causes, Armand finds that he can't let him go after all, and still brings him into Hell with him, because he still loves him half a century later and cannot bear the thought of facing eternity without him.

(Please imagine gifs of screaming cats and people falling to the ground screaming for this.)

I also love the idea that Armand, who for so long was reduced to his looks and his attractiveness, loving old Daniel not despite his visible age but because of it. Because Daniel was allowed to do something that Armand never had a chance to do: to life a full though imperfect human life.