rhyme – A riddle like an Erysimum

Perhaps you are

WALLPAPER?

I envelope the inside
Like a reversed hide

The skin of a room, but here the skin is on the inside not the outside.

I can start anywhere
If I don’t, notice there

You’ll certainly notice if part of the wall isn’t papered. (I am not entirely satisfied by my understanding of these two lines, though. Perhaps there’s something cleverer meant here, or perhaps my answer is wrong :-).)

The antagonist of bare

A papered wall is in some sense the opposite of a bare one.

I used to bond by mare

Glues, including ones used for affixing wallpaper to walls, used to be made by boiling down horses’ bones.

The riddle is “like an Erysimum”

because that’s the genus of the _wall_flower. (For that matter, many wallpapers have floral designs, and you could describe those fairly literally as wall-flowers.)