Kylie Jenner Crashes Justin Bieber's Boys Night Out, While Selena Gomez Hangs With Niall Horan

Kylie and Justin snap pics, while Selena rocks out to Katy Perry with Niall.

It seems that Justin Bieber's boys night out was crashed by none other than Kylie Jenner.

Fresh off his trip from the Cannes Film Festival and her trip to Paris and Florence for sister Kim's wedding, Justin and Kylie hit up the iconic Rainbow Bar and Grill in West Hollywood, California. And lucky for us, they snapped photos of their night out for the world to see.

Kylie first tweeted out a selfie of herself and Justin looking cozy together at the bar, while Justin later posted his own photo of himself, Kylie and John Shahidi, the founder of the photo-sharing app, Shots, which Justin is an investor in. The caption for the photo read, "Boys night out."

This isn't the first time that Justin and Kylie have hung out together. Earlier this month, Justin uploaded a photo of himself, Kylie and model Yovanna Ventura -- whom he gave an Instagram shout-out too earlier this week -- at a Floyd Mayweather Jr. boxing match.

And while Justin was hanging with Kylie, his ex, Selena Gomez, who unfollowed the Jenner sisters and Justin on Instagram after what was thought to be a fun-filled weekend at Coachella, was reportedly hanging out with another pop star: One Direction's Niall Horan.

The two were supposedly spotted at Katy Perry's Prismatic World Tour at London's O2 Arena on Tuesday.

Back in February, Selena and Niall were photographed posing with some fans on the streets of London, which sparked rumors that the two may be more than friends.