Gambangeseo Namjajuingongeul Mannatseumnida

One day, I opened my eyes and found myself in... prison?! That's right. Out of all the characters I could've reincarnated into, I woke up inside a 19+ rated romance novel as the villain's younger sister. To make things even worse, I was locked up inside the infamous Kambrakam Prison for my brother's crimes. Deep within the very same prison lies Henrich Doran von Hel, who's rumored to be suffering from a curse that turns him into a beast. In the original novel, he's supposed to meet the female lead and spend an erotic night with her here in prison... but of course, the plot's gone awry thanks…