A must read - even if you aren't really into the original story, for a number of reasons:
1. It's easy to understand
2. You can't really go wrong with five chapters
3. The entire approach to the story is very different
MaruMaru has destroyed Yuno before the story kicks off - no Yuno present has put Yuki in emediate danger.
Whilst work has been put into place to bring Yuno back and restore a critical Yuki, MaruMaru and Akise replace the two leads.
This story is simply a case of the same scenario's witnessed in the begining of Mirai Nikki, only very different characters put into place to deal with these set-up.
A vast contrast to the original, were we are use to the; out-of-place innocent that is Yuki and the, one-girl-army that is Yuno progressing threw danger. Within this story, we have Akise; a smart boy who's genuienly interested in the situation he's now in and isn't too worried about his own safety, aswell as the supernatural, problematic-yet-sensible MaruMaru who's pretty independent as a main.
Futhermore, this story, despite being just five chapters, manages to utilise those characters who, for obvious reasons, weren't allowed a great deal of attention within the original story.
The art is fine, it's what we're use to in Mirai Nikki - the scenery isn't too special and the character design is a tad basic, but the characters styling stands out and they all look different.
I realli enjoyed this personally, more so then the original story.
The set-up of this lacked the idealism what is pretty much needed within this story; not simply because this main isn't 'part of the game' but because the main isn't the type that comes along too often in shounen's - sure we get the odd few smart leader types, but not too many are; very social, intouch with their feelings, 'career' motivated and generally humble.
I also liked the fact that dispite this manga being short, there was a begining, middle and end, also, this story does have some stand-alone qualities; you don't need to complete or even enjoy the original in order to follow this - you don't even have to reach the half way point really?
If you have ever picked up the Mirai Nikki series, no matter what you think of it, this is must!
A good, well written story that without a doubt deserves a series of anime specials of it's own.