it's awesome, I discovered it at the time when it was released on furaffinity. it deserves a part 2 to go up to the size of the universe and more, with the absorption of the cosmos, the body of the goddesses who become the source of reality and obtain the power to reorganize it ;)
This is more fascinating than hot. Lots of prehensile tail action combined with creative ways to absorb. It's a unique and creative approach to absorption, turning everyone eaten up into a consenting hive mind (at first). Sonic's arc is pretty damn funny, especially when you realize it's pretty much just him. Where it falls short for me is at the most important parts for growth, it's mainly tail growth and giantess. Meanwhile the boob growth doesn't truly kick in until mountain and continent size, ass growth barely happens, and there's no belly growth or weight gain at all (which isn't everyone's things, understandable).
TL:DR - unique and creative premise and science, worthy studying, but personally I wanted a different kind of growth progression