The Lazy War God Son-in-Law

Barbarian forces invade the Great Zhou Dynasty border. Jasper Lin, husband of female general Ruby Ye, hides his true strength via a slacker System Interface, mocked as a freeloader. He grows stronger via the System Interface. When Ruby Ye is transferred, barbarians breach the city. Jasper Lin stops hiding, summons Azure Cavalry Elite, breaks through barbarian troops, slaying the Centurion Commander. He leads civilians to retreat, hailed as the strongest Dependent Son-in-law.