My understanding is that there are actually two series.
Did the first series, which was in a monthly mag, get the boot?
If so, did the mangaka decide to start over when the series got picked up by the new mag?
In Chapter 5 (I Won't Get Pool Again) of Wagatsuma-san wa Ore no Yome, the following scenes appear on page 11. In that scene, the person being called Sakamoto is actually called Itou.
I guess it might be some kind of parody. Which character or…
At the first timeslips he had that suburban life with Ai, but later on, the timeslips were getting more and more locked until he gets to the "goes to Africa and dies" inexorable ending.
Supposing he changed the future only when he acted on info…