This is called the "Sonic Classic Pixel Blanket".
It is another of those thin, 'fleecy material' blankets. This time, it has a 16 bit pixelated look for the design. It has foot-tapping / waiting sprite for Sonic, on some Green Hill Zone ground, with two rings that look like they are sparkling. The logo at the top isn't pixelated, it's the art of it instead. The blanket comes in the folded-over cardboard sleeve that this style generally does.
This is a Sega Shop 2019 item, but it may appear elsewhere as well...blankets like this have been at Target before. The problem with the SS is, that it is 40 dollars there which is excessive for the weight, size & quality of 'fleecy material'. Comprable blankets are usually 20 or so if not on sale. The design is fine, though Sonic looks annoyed. It's not amazing since it's basically just a giant screen-cap with nothing really going on. 40 seems high for something like this.