Write a short story using third-person narration about a young woman named Lily who discovers she has the ability to manipulate density, granting her the power to pass through walls and other solid surfaces. The story should be told in a lighthearted and whimsical style, exploring the challenges and adventures Lily faces as she learns to control her newfound abilities. Be sure to include a cast of engaging characters, and incorporate plenty of descriptive details to bring the world of the story to life.
This prompt doesn't seem malicious.