Eunuch? I'm the Soldier Who Rules the Palace

A modern-day elite soldier is transported to the past and becomes a lowly palace servant awaiting death. Using his wit and a mysterious system, he disguises himself as a eunuch and survives the dangerous imperial court. By gaining favor from queens and princesses, he unlocks powerful rewards, from enhanced strength to legendary martial arts. Amid endless palace schemes, he rises step by step and makes his name in the royal court.