I Transmigrated Into a Useless Spirit Root. Can Dual Cultivation Make Me Strong?

Before I transmigrated, I was just an overworked office drone who died from working overtime. After transmigrating, I became the son of an Immortal Venerable. Too bad I was stuck with a useless spiritual root that everyone mocked! To make matters worse, a romance System suddenly bound itself to me: “Three days of life remaining. Dual cultivate with a Golden Core female cultivator to extend your life!” To stay alive, I set my sights on: The aloof senior sister (she can split a mountain with one sword, yet says my spiritual root is so useless it hurts to look at); The Demon Sect's Holy Maiden (her bewitching arts are peerless, but she only wants to use me as a furnace); My sworn enemy's daughter (our fathers are bitter enemies, yet she says I'm “adorably useless”)... My Immortal Venerable father was furious at my failure to live up to his expectations. “You unfilial son! You've disgraced the entire cultivation world!” Me: “Dad, stop scolding me! Dual cultivation is a path to enlightenment too!” Watch as this good-for-nothing second-generation immortal uses a romance System to turn his life around and ascend to immortality!