Rihanna covers No Doubt and Kings of Leon at karaoke

While on her “Diamonds World Tour,” Rihanna stopped by a karaoke bar in Cologne, Germany -- and by the looks of things, she was having the time of her life performing tracks by No Doubt and Kings of Leon.

“She had just ordered some drinks and fries for the table then just decided to get up and sing,” a witness told the Mirror. "It was nice to see her having a lot of fun and she was clearly enjoying herself on her time off."

The 25-year-old songstress lets loose while she and a friend belt out No Doubt’s 1996 classic tune “Don’t Speak” and King of Leon’s hot track “Sex on Fire." Fans seem to like like seeing Rihanna in party mode.

“She's perfect,” one viewer commented. “I love the way she doesn't even care about anyone or anything, and I bet if she was sober she would give the same sh-t about it. <3”

Wrote another: “Love the way she's having fun hahahah would be fun to hang around with her.”

This isn’t the first artist to be has been seen at a karaoke bar covering classic tunes.

Last year, Katy Perry took on Will Smith’s ‘90s jam “Miami” while visiting a Catalina Island bar, and Usher delivered a crowd-pleasing rendition of The Jackson 5's "I'll Be There" at a Los Angeles establishment.

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