Do you have siblings who you just can't help but hate a little? Well, in Desire's and Dream's case it's a bit more complicated than that.
If you didn't understand Desire's motives to get under their sibling skin, you were not alone: a lot of people who weren't familiar with the original Neil Gaiman's comic series beforehand felt like there was quite a bit of information left out as to why exactly Desire wanted Dream to spill the blood of his kin. To really get Desire's motivation, one should read the comics – at least The Sandman Overture, where, according to Gaiman himself, the answer is. But if you have no time to check out the writer's hit comic series, we got you covered.
What was Desire's plan, anyway?
In the Netflix series finale we find out that the whole thing with Rose Walker being a vortex was Desire's plan all along: they violated Unity Kinkaid while she was sleeping, they, in fact, created Rose as the vortex, all in the hope that Dream will have to kill the vortex thus spilling the blood of his kin.
While it does sound like a terrible thing to do, to kill someone related to you, the viewers don't actually get to learn the consequences of that deed. In the series it is never explicitly explained why exactly this deed would be Dream's undoing. Well, the actual thing is, by spilling the blood of his kin, unknowingly, Dream incurs the wrath of the Harpies, who hunt him down and kill him.
In the comics, this plan was certainly not the last Desire's attempt to lure Dream into getting himself killed. So why do they hate their sibling so much, working so hard to get rid of him?
The reason is heartbreaking enough
One of the greatest things about 'The Sandman' is how we can – to some extent – actually feel some compassion towards its villains. Everyone in Gaiman's world has a solid, understandable and sometimes even relatable motive driving them, Desire included.
The Sandman Overture Desire's motives are explained clearly. The readers learn that Desire made quite a few attempts to save the universe, and each and every time they asked Dream for help only to face a refusal. And yes, the worst thing about it is that Desire doesn't even remember it all, but the anger they feel is not going anywhere.
Again, it wasn't the first nor was it the last time Dream refused to help Desire; there's quite a lot of bad blood between the siblings, certainly enough to explore it in 'The Sandman's season 2, should the series be renewed. The finale sets up 'The Sandman's season 2 perfectly with at least two story arcs (Desire-related and Lucifer-centered) to focus on. However, as of this moment it's not clear whether Netflix is going to renew the series.