For some reason it's in the "background" layer, but I think it belongs in the "ground" layer with other, similar items like:

Unlike the other three, it doesn't seem to touch the ground either

That overlay is just weird

I thought it was like this because you're technically supposed to layer it behind your HA? Hence why it's oddly up in the air like that

yeah, it looks like it's intended to be layered behind the HA, but it technically is on the "ground," just a little further back in perspective from the HA, hence why it appears to be floating. the thing is, the fox stone and the old gray portrait are also layered behind the HA, but are also on the ground and so they are considered "ground" items, which i think makes sense. so, for the sake of consistency (not that we have a ton of that in the first place, especially not with regard to wardrobe layers), the zebra should be on the ground layer as well.

That's exactly what I was thinking, and why I included them as examples. The background layer is mostly for actual backgrounds and scenery. "Ground" is more for props and familiars. The zebra is completely out of place, imo.