I Weaponized the Tyrant, But Forgot the Timer

I didn't ask to wake up buried alive inside a massive, sealed hourglass in the subterranean academy of Ghalib. But since my political enemies put me here to die, I decided to use the quickest, most efficient tool for revenge: Davran. He was a feral, discarded boy whose veins had been pumped full of liquid shadows by dark-magic researchers. My plan was simple. I’d use my intellect to teach him how to control the abyss within him, raise him to usurp the Parsad throne, and then quietly retire to sleep my days away with my pet drake, Gohar. It worked perfectly. A decade later, Davran is a towering, ruthless Emperor who crushes our enemies and dotes on me. But there are complications. Minal, a reincarnator desperate to 'fix' the plot, keeps trying to make Davran a benevolent ruler. Worse, nobles who call me lazy have been mysteriously turning up dead in pieces. But the biggest problem? I just coughed up black sand. Nobody mentioned that surviving the hourglass cursed me with a hidden, fatal time limit. Now my expiration date is approaching, and my sweet, obedient weapon has discovered the truth. Will his obsession shatter the world just to keep me breathing?