The story is basically about a world where people couldn't die nor reproduce, and there is a little girl named, Ai (a gravekeeper). One day she met a person who have the same name as her father.
Project page is here: http://www.baka-tsuki.org/project/index.php?title=Kami-sama_no_Inai_Nichiyoubi
Here's a bit of the first volume's prologue.
God created world on Monday.
God separated order and chaos on Tuesday.
God defined the numbers on Wednesday.
God allowed the flow of time on Thursday.
God looked over at every corner of the world on Friday.
God rested on Saturday.
Then, on Sunday, God——
The place was like a natural cemetery.
Originally the place was a lush, fertile hill, but at present it was densely covered by overgrowth, with boulders scattered all over. Arid wind blew through the remnants of living beings, a tree stood straight in solitude on the bald hill, not a presence of a single human could be sighted.
Just to restore the forest to eighty percent of its former glory would take over a hundred years. That was how barren the land was.
In a corner of this piece of land, a gravekeeper was currently waving her shovel with great efforts.
The job of a gravekeeper, of course, is to maintain the cemetery.
The girl continued to try her best to dig, using her entire strength she stab the shovel into the ground, then using it as a lever to scoop up the soil into the basket.
Ai kneeling down on the ground, exhaled out, proceeding to gaze at the western horizon. Reflected from her sight, she could see the sun setting, the breezing wind also began to feel cold.
Ai with an expression full of resentment looked at the setting sun, after a while she forced herself to get out of the pit. The surrounding was composed of similar looking graves.
Taking a glance at the countless graves, Ai muttered to herself.
“Job done!”
Carrying the equipments down the hill. At the foot of the hill was a wooden cabin and a well, there Ai used it to clean the equipments. These tools had been used for a whole day as such it was dirtied black.
Ai using her hands, she soaked the equipments in water, then grabbed a stool and a brush over while rolling up her sleeves. After a good while of preparations, Ai washed the equipments clean. Washing away the sediment, laying it out in the sun, also lubricating various parts of the equipments. She groaned as she swiftly carrying out her tasks, the pail, the sickle and the hoe was sparkling under the rays of light.
At last Ai lifted up her partner.
The shovel.
The shovel was of a simple design; a wooden shaft with a silver metallic head, on the surface patterns of trees and roots were engraved on it, an evidence supporting her claim as a gravekeeper.
Ai carefully washed her beloved shovel.