It is important to watch Soul Eater Not! Like wanna know how Sid became a Zombie? Or how Liz and Patty meet Kid. Watch Soul Eater Not! It explains that. Not gonna spoil anything. I know it's a spin off series, but it takes place before the original SE Series. I say it is worth watching. It explains some character back story that the original series didn't explain much of. Like remember how an episode where Soul scared Maka cause of explaining how Sid died. Well.... Will just leave it to Soul Eater Not to explain back stories the original didn't explain. Also I believe it was in Episode 3 or SE that showed Sid as a human. It was confusing not knowing how he became a Zombie in the first place. I am glad Soul Eater Not cleared up character back stories. Not talking about the Manga's point of view. Just the Anime's point of view on this. Also Clay and Akane look like Adult Naruto and Sasuke. I do like the character designs as well. You should think of this as a different series all together. And not the original Soul Eater series. I also like how it goes into details about characters we would of never known in the original series. This SE Not! Spin off series is important if you stop to think about it. Instead of think oh different show, different art style. Waste of time. Cause no it isn't. It has details about characters back stories. And deaths that you wouldn't of known otherwise. Any true tagahanga should consider that a win, win in a series. Heck I watch an like way to many Anime. And many different art styles of Anime. This is just no different from any other good Anime out there. Tsugumi Harudori Anya Hepburn and Meme Tatane. #IdonothateSoulEaterNot!