To Save Seven Villainesses, I Went Full Harem!

I transmigrated into a novel — “Tianyuan Continent: I Alone Am Supreme,” also known as “My Seven Wives Are All Villainesses.” I became the disposable villain who’s doomed to die in three days! Luckily, I have a system — and my mission is to save the world. If all seven heroines fall into darkness, the world will perish. So… I have to save them with love!