There is no story. Rather, it focuses a lot more on their everyday lives. There are two main "everyday lives" on this anime. The first trio are Mio, Yuuko and Mai and the other trio are Hakase, Sakamoto and Nano.
There are a lot of Slice of Life shows that are so boring. However, this anime takes it on a whole new level by making a lot of parts exaggerated and unrealistic which just works a lot. How? The humor of this show. I think it's safe to say that this show has the best comedy. I know, there's Gintama but, I have not watch that show (For how lengthy it is but I will watch that soon). There are indeed some parts on this anime that I didn't get but, most of the parts (Especially Yuuko's parts) are somewhat similar to my life when we get in on these situation. Except, this anime exaggerates it to the point where it looks unrealistic which is even funnier.
The animation of this show is top-notched as expected from Kyoto Animation. Sure, it isn't realistic but the art-style is very unique and it's sparks my eyes on how beautiful the artwork is. The animation fits the show itself. There are just many parts of this show that the animation looks like when they exaggerate a lot of parts like Mio running to get her notebook back. They didn't made it look simple. They made it like this is some sort of action film which, I was very impressed. The soundtrack of this anime is also outstanding. It just fits on every part of the show and the soundtrack aren't even forgettable. The opening theme is also very good. Hyadain did a great job performing both of it's opening themes which I find it surprising that even on the girl's part, it was him who was singing.
For the characters, I do admit that this anime adds so much cast but, I don't think they are forgettable. I can remember so many characters because the anime gives them the chance to shine.
I'll go with the first trio first. Yuuko is an energetic girl though, she's also lazy. She keeps forgetting her assignment and because of that, she copies her assignments from Mio. This is my favorite character of the series because on how I can relate to her a lot in a lot of her situations that she has been through. Mio on the other hand is the opposite. She is hardworking but, what they both have in common is that they are both energetic and cheerful. Mai is the quiet girl but, she is somewhat the troll of the series.
For the other trio we have Hakase Shinomoe. She is a Scientist/Professor who invents a lot of stuff like robot but, she's just a kid and has childish personalities which... can be cute for some. Nano is one robot of Shinomoe except she acts like human and she has a personality. She has a kind personality but, really disciplines Shinomoe well. Sakamoto is the pet of the three. He is a cat but, he acts old (Because he is older). However, that doesn't stop him from acting like what cats do.
Overall, I enjoyed the show. This show gave me a barrel of laughs. Even if you dislike Slice of Life, I highly recommend this show. It's not your ordinary Slice of Life which is ironic because Nichijou translates as My Ordinary Life.
Score: 9.4/10
