Genius mathematician x secretly ruthless prison official
Si Yan managed to scrape by on the meager inheritance her father left her until she passed the entrance exams for the Quantong Bureau of Currency and became a ninth-rank clerk. The pay was paltry, but at least it was enough to get by.
She had just collected her pay and bought some paper and charcoal pencils. On her way home, she witnessed a murder. The killer raised his hand and brought it down, not with a blade, but with a fan. Blood sprayed three feet into the air, yet he only murmured, "What a pity about this fan painting."
Most importantly, one sudden glance from the murderer scared her so badly that she dropped most of the paper and charcoal pencils in her hands. That was supposed to last her the whole month! She ran away, heartbroken.
To her surprise, just a few days later, she saw the murderer in the government office, dressed in a blue official robe. She recognized its pattern: he was a fifth-rank Director of the Jing'an Bureau, fully six ranks above her.
Lin Shu held Si Yan's book, Records of Strange Numbers, and smiled warmly. "Clerk Si, keeping a private record of discrepancies in the accounts is punishable by thirty strokes and suspension pending investigation."
Si Yan's legs trembled, and her voice quavered. "T-This subordinate was o-only checking the calculations..."
"You have a fine face, but it's a shame you stammer." Lin Shu put the book away.
"?"
"Would Clerk Si do me a favor? In exchange, I won't let anyone else see this book."
Si Yan swallowed. "My lord, can I claim reimbursement for paper and charcoal pencils?"
"..."
Theme: Act according to your heart.