Lu Shaodong’s mechanical genius spread through the underground car modification circles of Beijing like wildfire. He could diagnose a microscopic valve leak just by listening to the engine's hum, and he could tune the most aggressive horsepower out of the cheapest parts. But he always remembered his promise to me—no more dangerous games.

That was until I found it: a professional-grade miniature vacuum pump, a piece of equipment I had been dreaming of for my lab, sitting mysteriously on my experimental bench.

"Where did this come from?" I stared at Lu Shaodong as he helped me organize some wiring, my gaze sharp and accusing.

"Found it," he said without looking up, his tone casual. "Probably some senior student threw it out after graduation."

"Lu Shaodong, this thing costs fifty thousand yuan. No senior is throwing this in a hallway." I snatched the wires out of his hand, forcing him to meet my eyes. I saw the faint red veins of exhaustion in his eyes and the motor oil beneath his fingernails that was deeper than usual.

He was silent for a moment, then let out a self-deprecating laugh. "Yin, I just didn't want to see you working as a teaching assistant for that fake Vice President just to save up for lab fees."

"So you went back to underground racing?" My voice was trembling. I knew that world—roads on the outskirts of Beijing with no guardrails, no insurance, and prize money won at the cost of lives.

"I have it under control." He tried to reach for me, but I stepped back.

"You don't! Lu Shaodong, if something happens to you, what do I need this vacuum pump for? What do I need this physics degree for?" I shouted, tears spilling over.

He froze, a flicker of struggle in his eyes. Just then, his phone buzzed. It was a text from the head of the 'Shadow Crew': "Last race. 'Ghost Peak' pass. Win, and the prize money doubles. Lose, and you leave your right hand behind."

"Don't go," I pleaded, gripping the hem of his jacket.

"This is the last time." He cupped my face, his forehead resting against mine, his voice low and resolute. "That money will cover your tuition for the next four years. I want you to stand tall in this city, Ling Yin. I don't want you looking at anyone's feet—including your mother's."

In that moment, I knew I couldn't stop him. That streak of "sacrifice" in his blood was his way of loving me, but it was also a blade that cut me deepest.

"Fine. I'm going with you."

"No!"

"If you're going to gamble with your life, then take mine with you." I put on the titanium glasses he gave me, a streak of madness in my own eyes. "In physics, momentum is conserved. If your car is going off a cliff, I’ll be the mass that changes the trajectory. I'm the only variable."

That night, Mount Dongling.

The mountain wind cut through us like a knife. A row of modified monsters roared on the starting line. Lu Shaodong sat in the driver's seat, and I sat in the passenger side, pulling the harness tight.

"Scared?" He gripped the steering wheel, turning to look at me with a gaze of frantic tenderness.

"As long as you’re here, gravity exists," I whispered.

The light turned green.

The car launched, the G-force pinning me to the seat. Lu Shaodong transformed. He wasn't the boy who cooked noodles in a basement anymore; he was a god of speed. Every turn, the scream of tires against asphalt tore at my nerves. The chassis slid inches from the edge of the abyss—a true dance of death.

In the final hundred-meter sprint, I noticed he wasn't just accelerating. He was staring at the rival in the rearview mirror.

"What is he waiting for?" I thought, my heart stopping.

"He’s waiting for the chance to end this forever." Lu yanked the wheel, using a precise inertial drift to block the opponent's line while utilizing the gravitational acceleration of the downhill slope to push the car to its absolute limit.

The moment we crossed the finish line, the world went silent.

The prize money was won. His hand was safe. And I, under the starlit sky, was vomiting my heart out on the snow.

Lu Shaodong knelt in the snow, holding me tight, his body shaking violently.

"I'm sorry, Owl. I'm so sorry," he repeated over and over.

"Lu Shaodong," I gripped his collar weakly. "From now on... we only study statics, okay? No more motion."

He laughed, tears in his eyes. On that desolate peak, for the first time, we felt the true weight of being alive—far beyond money or power.