WATCH: Shawn Mendes Proves He's A Bad Boy At Heart After This Argument With An Autograph Hunter

15 June 2017, 12:04

If you've learned one thing today, it is to NEVER get on Shawn Mendes' bad side.

Shawny boy must get swamped by hundreds of fans every day asking for selfies and autographs. So, the question is, how do you separate the genuine ones from the fakes?

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When approached by a man asking for an autograph, Shawn decided it was a chance to double check the guy genuinely wanted it and wasn't just going to sell it online.

Shawn is heard saying, "I love my fans and I do everything for them. People like you, you sell the signatures." Not happy with the star's behaviour, the man revealed he actually wanted the autograph for his sister.

Mendes adds, "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***ing lying."

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Shawn's tirade didn't end there, he stated, "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**k. You know nothing about me. So how do you think you have the right to say anything about me? 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".

Being the sweetheart he is, Shawn finally signs the photo for the guy's sister after a brief phone call but his heart was in the right place, and for that...we salute you!

Watch Shawn Mendes amaze 80,000 screaming fans at Capital's Summertime Ball with Vodafone.