We all know Justin Bieber loves his fans, but he took things to a whole new level on Monday afternoon when he left his Beverly Hills hotel, picked up a pair of girls off the street and took them to the Beverly Center in Los Angeles!

Bieber's driver called out to the ladies initially, but it was only after the 20-year-old pop star rolled down the window of his 2015 Cadillac Escalade and hollered that they came over. But rather than dropping some serious dough on the gals once they arrived at the mall, the group split up! The two girls stopped by the Louis Vuitton store and then headed back to Bieber's chauffeured ride, but they stood outside the SUV for nearly an hour while he continued shopping with his entourage.

Our X17 photographer on the scene tells X17online exclusively:
    "Bieber definitely hooked up with these girls the night before, even though he could do way better, which might explain why he ignored them the entire time he was shopping and kept them waiting. He usually flaunts his flings in Selena's face, but he was actually embarrassed about this and clearly trying to hide it."

And that's not all! While inside the mall, the 20-year-old singer Instagrammed a photo of gorgeous blonde model Danielle Knudson posing in an ad campaign and wrote, "Who is this Guess Model. She's Stunning." Well, we just answered Biebs' question, but it seems like he wasn't posting that just to find out her name.

Seeing as ex-girlfriend Selena Gomez is currently posting sexy vacation pics from St. Tropez, it would seem as though this was his way of firing a shot back at her. And since he's uploaded pics of himself with skankalicious chicks and she can't stop Instagramming memes and texts about love and relationships (not to mention snapshots of her jet-setting all over Europe with model Cara Delevingne and several unidentified men), we're curious to see what she puts up next.

Justin religiously watches Selenas every move on social media -- so this is no coincidence, a source close to Jelena told TMZ earlier this month when the former flames started their campaign to make each other jealous via social media.

Your move, SG...