Tags: recon facebook twitch
First visit his Facebook page, he has this comment: "Do u know about twitch.tv? Sometimes streaming there, look at me!"
The about page writes: "Screen Name: pipissimo (Other Service)"
So you can find his twitch profile: http://www.twitch.tv/pipissimo
In one of his previous videos (the only one with a comment): http://www.twitch.tv/pipissimo/b/514722428 at 22:41 you can see that he shows a paper with the following text: "EVERYBODY HATES MY GUITAR SOUND" and this was the flag.