Draco had never thought himself as a jealous chap, or even an overly possessive one. Harry changed that, in the blink of an eye. One look at him wrapped around Ernie MacMillan in the newly repaired Conservatory and Draco was a changed man.
Or, at least, a different man. A darker one, all Light eclipsed.
An evil bastard of a man, with a scheme to force Harry away from all those other blokes, the ones who panted after him endlessly, and all the bints, too. It was the plan of a thoroughly rotten git, one with a skewed moral compass and questionable ethics, and one which could only be accomplished by a fellow knowledgeable in both Dark Arts and Potions. Intimately.
By blood and by nature, Draco realized; he was territorial.
It must a measure of his own craving for Harry's body that he'd never once suspected it.
It wasn't even that he was a Slytherin, though that certainly contributed to the complexity. Slytherins weren't, by nature, evil or bad or Dark, but they were crafty and they were deep as houses.
It wasn't even the Malfoy sense of entitlement. Draco'd always been highly possessive of the things he favoured, but this went well beyond it. He worried, ever so briefly, he'd approached the raging madness of his poor doomed Father, beguiled by power, with this overweening desire—and then ventured beyond it. Except instead of Death, the snuffing of existence, he'd give Life. He'd mete out Harry's future in such as way that would always leave Draco in control of it.
It was stupidly simple, Draco's grand plan. Almost as easy as badges.
Simple, blindingly, beautifully simple. He'd have Harry up the bum in a winking; get him saddled with Malfoy child and then see how he liked it, the little twat. No more Ernies nor Justins, nor Weasleyettes, ever. They'd be tied for life, he and Harry, and no one—but no one—would ever be able to break that particular bond, not even Harry.
Especially not Harry.
And Harry would be Draco's, for ever after. For Life.