Oh, my gosh. I am blown away at this amazing story. Seriously! It's fantastic. I love the way you intricately describe everything. It gives a really good picture of what things look like and how they work. I have to admit though, I was a bit confused at some parts, so be careful when describing an idea, device, or anything similar. You might end up over complicating it if you drag it out too long. I would say the characters are written pretty well. I just think that both human characters have very similar character traits. Not that that's really a bad thing, but it would probably be nice if you gave the main character a few different traits. You could have made him really sarcastic or funny. And you could have made Yuma less interested in this space mission stuff and have her be more eager to leave and you could even have her act rudely to Link showing that she doesn't like technology or robots very much. Then again, I can tell both characters have different traits and their own personality, so there's no need to change it if you really don't want to or don't feel the need to. I did also notice this story really lacks a strong conflict or antagonist. I can totally see why it would be difficult to think of a conflict or antagonist for this particular story. Still, I think you could have added something like Link going missing and they find some sort of predatory robot creature which attacks the robots on the planet. Then you could have Z and Yuma go to rescue him. You could even go a step further and establish a character arc for Yuma, showing how at the beginning she wasn't too fond of Link, but actually starts to like him towards the end. And you could also have an arc for Z. You could have it that he is really startled, by the idea of "linking" with Link, but at the end he has to link with Link and actually begins to enjoy it and uses the ability to aid in rescuing Link. I know that goes really far off from what you already wrote, but I just wanted to share my honest thoughts. It's alright if you don't feel the need to change, or add to it. Other than that, this story was a hecking blast to read! There's a very unique plot to it and I love that the most about it. Keep up the great work, dude!