The creepy art was great. I like the setting of spoopy librarians wanting you to be quiet, and the footstep mechanic was relatively easy to pick up. I found the footstep SFX really distracting, they could have probably been toned down a bit. I didn't find the levels particularly challenging (no need to use the run). A few more levels exploring the mechanic further would have been nice. I liked the ending!
Here's a playtest