A Shinigami opposing his job and instead saving a person from death? Awesome idea! I really liked the setting and it's unique as well. I even reread it once already because of the overall idea.
However, sadly, the execution was poorly done. The story focuses way too much on how Eiji wants to repay the Shinigami. Not much more than that happens, it's always Eiji thinking about their relationship. Because of that, he has a rather shallow personality. While the mangaka obviously tried to give him more depth by adding scenes of Eiji at work, it didn't really get across to the reader. He's more like... a bit dumb. And never listens to what others tell him to do.
The character design of the Shinigami was way more interesting, though he as well lacked something. It would've been interesting to know why he wears that mask, so that it's not only to make him look cool (which he does).
I would've wished for there to be more Drama and less pretend lovey-dovey. "Pretend" because it's more like... trying to be full of love but ending up a bit shallow? The first and last chapter were better, though. I also would've liked to get to know more about the backstory of the Shinigamis and their ranks. Probably using more characters than just 3 would've been better as well (I'm not counting the 1-page characters in the restaurant).
The smut scene's only purpose was to implement a smut scene. I felt like leaving it out and making the manga Shounen-Ai instead of Yaoi would have benefitted the story a lot.
Another thing to mention is the poor translation (which is obviously not the Mangaka's fault). While one could understand everything (which is not a given, I've read much worse translations than this one) there were many grammatical and spelling mistakes. Some situations also sound strange if the reader is not familiar with basic Japanese or japanese culture. For example one time the Shinigami says "With permission" and enters a room. I guess in the original he said "shitsureishimasu" which means something like "Excuse me...". I cannot say for sure, but it makes a lot more sense and with the translations as it is, it sounds like there was a strange secret talk between Eiji and the Shinigami. So, while the translation is not that well done, I'm happy that it exists.
To end with something positive: The art was good. I really like the way the shadow looks like (even though it sometimes seems a bit pixelated compared to the rest of the page? Might be because of the scanlation, though) and it was pleasant to read.
All in all, the manga has a lot of flaws. Seriously, for being quite short, a lot. It could've been a complex, deep and interesting story, but it took the easygoing romance path instead. That will not keep me from rereading it though, because I like to look at the art and think about the idea itself. If this manga were to be redone and improve the storytelling, it could easily be one of my favorites.
So, if you also enjoy reading mangas because of their ideas and maybe think about it a bit afterwards, give it a try. If you want a full-fledged manga with a serious, solid storyline, you should rather go look for something else.