waltz in(to some place)
To enter (some place, establishment, or event) in a particularly casual, carefree manner. He came waltzing into class nearly 20 minutes late, acting as if nothing were out of the ordinary. I've spent my entire life training to be where I am, and this young kid just waltzes in like it's a hobby of his.
Farlex Dictionary of Idioms. © 2024 Farlex, Inc, all rights reserved.