Justin Bieber strips down his hit single “Boyfriend” in a performance on The Ellen DeGeneres Show that aired on Tuesday (January 29).

The 18-year-old singer was there to promote his brand new album Believe Acoustic, which shot straight to the No. 1 spot on iTunes after its release that day.

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The day before, Justin showed off his abs while lounging around a Miami hotel in his underwear.

Watch Justin sing his acoustic version of “Boyfriend” below!