Guarding the Newbie Village: None Shall Pass

[Power fantasy, System, urban high martial arts, decisive and ruthless, almost demonic intelligence, overwhelming intellect, multiple heroines, tangled romantic rivalries, dark demon lord, psychological torment, defeating stronger foes, villain protagonist, cold-blooded, dark aesthetics, anti-cliché antihero, human nature as a catastrophe] A demon-king saga of hundredfold scheming and meticulous plans, with psychological warfare so devastating it cuts to the heart like a demon. A terrifying mastermind who turns his enemies' lives, dignity, and even humanity into pieces on his board. His schemes are as precise as clockwork. He treats people as pieces and commands them with a whole arsenal of techniques. His control of the pace is tyrannical: even when you know he's moving the pieces, you have no choice but to enter the game. [A revenge journey of surviving and striking back, challenging stronger foes] + [a battlefield of love between a yandere, devoted loyalist and a beautiful, venomous woman] Male lead Gu Qin: an absolutely self-serving, cold-hearted demon lord. His harem: a beast-eared loli sword maiden, a gentle big sister from next door, and a seductive, mature noblewoman. More heroines to come. Witness how a genius driven mad by the world uses his intellect to turn the entire world into his hunting ground. The strong and weak trade places, and foes are killed on the spot. He rises from despair, consumed by darkness. After obtaining the Garrison System, he launches an utterly merciless revenge, building towers of enemy skulls to deter invaders. No matter how many come, they are all just more material for the towers! He manipulates two fronts at once, and one scheme leaves a thousand dead. As long as there's bait, it doesn't matter how many come or how strong they are. You're all pawns crossing the river on my board. Your lives and deaths are mine to decide. Cultivators in both the real world and the alternate world of the demon race are at their wits' end, yet the rewards for killing Gu Qin keep growing, tempting everyone to take him on.