Not as good of an afterlife-and-living-world-connection story as AnoHana, but it's not bad. It just seems like some things at the end are not fully wrapped up very well, and I just did not find it all that entertaining.
Story - 8/10
Majime na Jikan (in English "Serious Time" though I don't really understand the title after reading it) is a story about a girl named Kazusa who is one day killed in a car crash. In this manga, it turns out the first stage of the afterlife is right above our very heads: ghosts move about observing everything that goes on from a distance (or sometimes closer as with the case of the one perverted ghost as well as Kazusa).
The story basically just follows Kazusa as she tries to cope with being dead while at the same time trying to somehow find a way to help living mother cope with her death as well as helping other ghosts that she becomes friends with.
Art - 8/10
The character designs are good and the town that is often shown below when the ghosts are flying looks very nice. Nothing really stands out that much though, so there's just not much to talk about with the art.
Characters - 7/10
Being only 9 chapters, the characters do not develop much. It's more about them dealing with what has already happened, but as I mentioned before, it ends a little too soon to really clear up things for a few characters. About the only connection with Kazusa is when her mom is talking about all of the great things about her. Aside from that, she's not all that interesting of a main character. The other characters mostly have sadder pasts like a boy being beaten by a parent, 3 children burned alive by their mother who did not want them, and a man who got in trouble with the yakuza (borrowed money and lost it by gambling).
Enjoyment - 7/10
I did like it, and the part where Kazusa's mom was talking about her while looking at scrapbooks was really well done, but I was glad it was only 9 chapters so I could just finish it up in a day and move on to something else. It didn't provoke any emotions in me unlike AnoHana (sorry only other similar thing I've seen so I can't make any other comparisons), but I would recommend it if you like short stories about trying to cope with sad and sudden tragic events like the death of a daughter. It does have some comedy that made me smile, but not a whole lot.