The "Heartbreaker" singer, 20, shared a photo via Instagram of the "Nerf wars" he started with the two models.
"@kendalljenner why the need for two guns fool and @haileybaldwin good work today we were killin everyone. #nerfwars," he captioned the shot.
In the image, Bieber poses with a red Nerf gun facing the camera. His newly dyed platinum blond locks are hidden under a red flat-brim hat, paired with a white T-shirt and red basketball shorts. The pop star is flanked on either side by Jenner, 19, and Baldwin, 18.
The daughter of actor Stephen Baldwin (and cousin to fellow model Ireland Baldwin) went casual for the evening fun, wearing a pair of low-slung heathered sweats with a black T-shirt. Pulling her blonde hair back into a high ponytail, Baldwin took some inspiration from Taylor Swift, sporting the singer's trademark winged black eyeliner.
Kim Kardashian's younger half-sister, meanwhile, went incognito in an all-black outfit, wearing a pair of figure-hugging black pants paired with a zippered black jacket and hoop earrings.
The trio's Nerf wars took place just two days after Bieber denied rumors that he was dating Baldwin. Sharing a photo of himself with the blonde fashion model, Biebs wrote, "People are crazy. I'm super single and this is my good friend u would know otherwise."
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