Since it uses the comparative word "as" it is a simile.
The phrase went wrong somewhere, it was always, "cute as a bug in a rug" - meaning 'very comfortable' but someone in the 1940's corrupted it to what you've just said and it's now nonsensical. There's a similar saying, "As cute as a button" and "As cute as a bug's ear" but these
no a simile is when something is like something for example as snug as a bug in a rug meaning comfortable ( and a little humorous )
This phrase is contemporary and a simply internal rhyme with a literal meaning. It is more often heard as "snug as a bug in a rug."
bug rug
Rug, mug, dug, hug, jug, bug, thug rug snug bug come on that's easy!
rug size
hug, bug, lug, and rug
Bug Rug.
bug rug
bug, rug, smug that's what i can think now
gnat mat bug rug
hug bug rug