Time-Limited Genius Dark Knight

abusive family members abusive siblings annoying characters bad reputation brothers butlers calm protagonist capable male lead cliches dying protagonist dysfunctional family/ies european ambience full color game elements half-brothers half-siblings harem subtext knights lost memories magic maids male protagonist manipulative male lead medieval european ambience monsters necromancy nobility/aristocracy noble protagonist purple/violet-eyed protagonist romantic subplot scenario deviation secret ability self-awareness siblings sick protagonist skills smart protagonist strong father subtle romance sword and sorcery/magic swords system talents teenagers terminal illness training transmigrated as the villain/ess transmigrated into a game transmigration twins weak to strong white/silver-haired protagonist young male lead