Villainess Level 99: I May Be the Hidden Boss but I'm Not the Demon Lord Act 6 (Light Novel) by Satori Tanabata

After dealing with troubles in the Royal Capital, Yumiella has returned to Dolkness County to relax. But with one simple line, Eleonora alters the course of her life: “I think you’re the only person who could hold their own against yourself.”

An imaginary battle of Yumiella versus Yumiella begins! Stuck in her own mind, Yumiella is put to bed. She wakes up later to find that...her left side died?! Yumiella’s left half has wandered into a world between life and death, and she sets out to explore a mysterious kingdom in order to find a way to come back to life. Meanwhile, Yumiella’s right half is back in the living world, stuck with a half-paralyzed body and working to find a way to fix the situation. But her motivation is much more Yumiella-like—the battle against herself was left unsettled, and she needs to figure out which side would’ve won! Can Yumiella resurrect herself, and if she’s successful, what does that mean for the other residents of the realm beyond life?