Both are the most superb slice-of-life that i have ever read.
each manga has its own unique atmosphere and tells you wonderful storys that when they end you fell all fuzzy and warm inside.
Both are slowly paced slice of life series.
Due to its brighter atmosphere and the moé appeal of the characters, ARIA is a good choice for helping people get used to the genre before introducing them to YKK with its more mature and melancholy insights.
In truth, if one was to really think about it, ARIA and YKK are not actually similar from how it is presented or the feeling you get from it. However, the story's theme(?) is quite same - a slow, peaceful glimpse of a group of people who seem to find happiness from many small things. I think that alone is enough to try the other and experience both.
Storyline wise, they aren't at all similar, but YKK gives a similar vibe as that of Aria, both occuring in a futuristic world, yet giving a laidback, fantasy feel to it. Though Aria is much much better IMO, YKK is worth a second look.
Honestly there is no plot, you could say they're about nothing and turn away from them. That would be a mistake. These titles are relaxing and soothing reading matter that gives you sensesation that life isn't all about money, work even education. In both landscapes are feast for eyes. Main difference is in pace , both slow but YKK is more adult and based on inner thoughts of heroes while Aria is shonen slice of life with lot of moe. Same charm , different ways of achieving it.
both are relaxing slice of life with no action, but great characters and warm atmosphere.
These two are both very relaxing to read, nothing much happens, but together with the characters you can come to appreciate the beauty of the world. Definitely worth reading.
The legends of genre "Slice of life". They have a very similar atmosphere, although YKK are more melancholic. After reading one of them, you MUST read another.
Both stories feature lovable protagonists who value the little things in life and learn beautiful lessons along the way.
Both works are calm and relaxing, set in a future where some disaster struck the planet, but which carries a beautiful mood behind something sad.
The interaction of the cast is very cute and is a triumph in both stories, even if it's more subtle and more "internal" in Yokohama.
Aria has a stronger and more direct emotional charge, but they are still similar and incredibly touching, especially for lovers of the Slice of Life genre.