Cultivating in Reverse: My Sign-In System Wants Me Dead

Transmigrating into a glorious cultivation world sounds amazing. Flying on swords, achieving immortality, eating heavenly peaches... Who wouldn't want that?Except my new body rejected all of it. A sip of pure spring water felt like acid in my stomach. A bite of fresh spiritual rice felt like swallowing glass. A standard healing pill made me vomit blood. I wasn't bullied by my sect. In fact, the elders actually pitied me! But my body was so bizarrely broken that the only way I could survive was by chugging cheap tavern wine and gnawing on moldy, spoiled bread.I thought I was just cursed with the ultimate Trash Physique. Then, on my 18th birthday, the Sign-In System finally activated.I thought my transmigration cheat had finally arrived... until I saw the rewards.[Ding! Signed in at the Clear Cloud Peak.][Reward: 10 Heavenly Demon Blood-Burning Pills.][Ding! Signed in at the Forbidden Yin Valley.][Reward: One vial of Nine-Nether Flesh-Melting Corpse Water!]I was furious. Was this stupid system actively trying to assassinate me? Why was it handing me legendary suicide pills and world-ending poisons?But during a life-or-death crisis, I was forced to swallow one of those cursed Blood-Burning Pills. I braced myself for my meridians to explode. I waited for the agonizing death.Instead, my muscles turned to jelly, I face-planted into the dirt, and... I leveled up? That was the day I realized my transmigration wasn't a joke. I possessed a mutated constitution. My biology perfectly inverts the effects of everything I consume!That deadly suicide pill? It paralyzed me for ten minutes, but permanently purified my foundation.That flesh-melting corpse water? Tastes like premium spirit wine and heals my broken bones.That terrifying, untouchable villainess whose very tears are made of Calamity Poison? To the rest of the world, she's a walking natural disaster. To me, she's an all-you-can-eat cultivation buffet.Now, while the righteous geniuses fight to the death over a single healing herb, I'm at the auction house buying out their clearance bin of expired, defective, and cursed trash pills for pennies.The Heavens want me dead? That's fine. I'll just drink poison all the way to immortality.