The overall of the story is some kid that can turn back time by going to parallel universes, and him trying to solve everyone's problems. In a nut shell, there is a mysterious mountain on the beach. There is several groups trying to uncover its secrets. The main person's dad found out you can use a tool to turn back time. His dad went off somewhere, and everyone assumed he is dead. The son (the main person) gets the tool, and tries to fix everyone's problems with it but while keeping it secret.
The show basically has a given problem or multiple that happens with a person he cares about it. Then he spends multiple episodes solving it. For example, his mom killed herself after some events. He tries to stop that for obvious reasons. But sometimes after fixing it, he is sent all the way to the start.
So my biggest problem with this show is it can be very repetitive since you're seeing him redo things over and over. It also feels like no one grows since once the problem is solved, he is sent back to the start to fix a new problem while ignoring the old problems which is around again. I mean even the main character doesn't feel like he grown. The only thing that does grow is the story, but not by that much per show.
My other big problem with this is the show doesn't seem to know what it wants to be. It tries to be funny at times, then it tries to be a mystery, then it tried to be an action, and now it's trying to be a romance show. And by trying to do everything, it falls flat on everything. The main character goes from being dead serious to joking about sex in an uncharacteristic way in a split second.
As far as who should watch this. I think if knowing what I said above, you are still thinking about it. Then it is worth a look. Otherwise, it's a hard pass.
Someone pointed out this show is based on a game. There is nothing in the anime pointing this out. But even if that is the case, the show in my opinion can't stand own it's own feet.
I still stand by what I said above. If you're OK with what I said above, then go ahead. Beyond that I would say it's a hard pass.