That is Grant Ellman. His stage name is Grant Prezence. His dog is called Fozzie Bear.

I first saw him in the show of Max Igan, and in the show of Jeff Berwick. They both featured his video in their show, the song Grant had been working on, this one:

That was his first (not his first) small breakthrough. Since then, he collected only more fans. This was him 16 years ago:

So, his first breakthrough was at a really young age. But the people forgot, and he started all over, for himself, with some friends.

I made a playlist featuring most of his videos:
https://www.youtube.com/playlist?list=PLkdXc8nLP1jZTTlfNelixEz11CxeORlpZ