If there's one thing people should know about Shawn Mendes, it's that you don't mess with fans. The "Treat You Better" singer just proved yet again he's loyal af to those who support him and he's not afraid to stand up for what he believes is the right thing to do. And it all stems from a simple autograph.

So what went down was Shawn being his kind self, was hanging out, meeting fans and snapping selfies galore. One man came up to the singer and asked for an autograph. Now, normally if a member of the Mendes Army who has been waiting for literally forever to get close to him asked, he would probably say yes, with an adorable smile no less, as he's done many times.

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But Shawn didn't want to sign an autograph for this guy, since Shawn concluded that the man in question had plans to sell it and most likely end up charging a fan a ton of money for something the singer would have no problem doing for you know, an actual fan. Shawn is always down to take pics, but signing something obviously takes longer and he wasn't about to let this guy scam a devoted fan down the line.

"I love my fans and I do everything for them," Shawn says in the beginning of a clip someone in attendance recorded and shared on Twitter. "[But] people like you, you sell the signatures."

This is when the man insisted the autograph was for his teenage sister, a story the "Mercy" crooner wasn't buying. That's when Shawn went into defense mode and asked the man to simply prove that he actually does have a sister and the man desperately seeking the signature well, wasn't being all that nice about Shawn calling him out.

"Can you call your sister then for me? If you have a younger sister who wants an autograph and you call her and I can speak to her, I will sign the thing for you. I will right now, but you're f—cking lying. Why do you have to be such a d—ck? I'm a regular dude. I'm not signing it. I would rather have this conversation to prove to you —you're standing here telling me I'm going to have a bad career and that I'm a d—ck. You know nothing about me. So how do you think you have the right to say anything about me?" Shawn said. "Call your sister. It's so easy! If I call my sister in two seconds, she would pick up the phone so why can't you? If you have a younger sister, I mean it, I'll sign all day for her."

OK LET'S TAKE A MINUTE HERE.

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The Canadian cutie was not having any of this and wasn't going to back down until he got to the truth, which he did. The guy's supposed sister did answer the phone and Shawn spoke to her, so yes, he ended up writing down his autograph once he verified that this man's story was legit. It's obvious that his connection with his fandom who always has his back means the most to him and it's that heart and passion Shawn has for his music and everyone who supports his career that makes him so special. It's easy to see why his fans love him so much! At the end of the clip, he did turn to the fans who were patiently waiting for him to finish dealing with that guy and he said, "You guys know what I mean, right?" He literally turned to them for support in that moment and it was literally the cutest. So moral of the story: don't mess with Mendes. He'll throw it down when it comes to his fans. Mic drop.

shawn mendes thank you

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