My Master's Lazy Genius

Serena Morgan, without a Spirit Root, wants to slack off; her slacking triggers a Heavenly Tribulation. Caelan saves her, takes her as disciple. Serena, "exploited" by Master, creates inventions. A System awakens (cheating, consuming life). Caelan knows, teaches "Spirit-Devouring Art" to counter System, forge Pseudo Spirit Root. Serena, with "black technology," System buffs, Master's backing, becomes a legend. She and Caelan develop feelings, forging a path of comeback and romance.