The eunuch became a sage after checking in from the harem

The modern ordinary guy transmigrates into a lowly eunuch, relying on a harem sign-in system to gain opportunities for cultivation. While completing tasks assigned by the empress dowager, he practices to restore his male form. Along the way, he constantly thwarts life-or-death traps set by the emperor, defeats external enemies' humiliations, protects the empress dowager and the ninth princess, kills top martial artists, eventually overthrows the scheming old emperor, helps the ninth princess ascend the throne, becomes the regent, enjoys power and beauty, and avenges all the humiliation after transmigrating, achieving a perfect rise from the bottom to the top of the dynasty.