He is the same person as the guy who created the video. Manyakis is just an alias he uses for his hentai artwork, while SFW stuff he puts under his real name.
It's not a secret or anything, he just keeps his NSFW and SFW stuff separate, which honestly I think is better that way.
Though on a side note I find it odd anyone would create hentai for the Amazing World of Gumball but since the art is good I'm not complaining.