🤔Hmm, it sounded like the book 'Poisonous Medicine'. The female protagonist was proficient in medicine and was good at using poison. She was the most unfathomable Tang Sect expert. The male protagonist mastered all kinds of poison techniques and was very cruel, but he doted on the female protagonist very much. This novel only had ten chapters, which fulfilled the requirements of the question. I'm recommending it to you. I hope you like my recommendation. Muah~