Great Premise, poor execution; mostly in the editing
This type of anime has been done before many times in the past, However, After Lost is one of the worst most forgettable executions of this decade. There is good to it though so let me tell you what I liked about this before I go into the bad.
The Good
The premise is really great, not gonna lie. There are several underlying themes about coping, loss, understanding, and forgiveness. Underneath a few good episodes sprinkled throughout the series; I'm sad to say that's pretty much where the praise ends.
The Bad
The series feels empty, what I mean is the series has a hard time finding it's footing. For example, a few episodes start about like 15 minutes in so they had had to run those 15 minutes in this annoying grainy flashback. There are multiple times the series thinks it wants to drive but that only really happens for one episode. On top of that, we're expected to feel for characters we just meet and have very little investment in. This get's better near the end but it's a little late to do that in the series. The art is passible but the Animation is so lazy, I thought a production as high as this one would at least reanimate a scene if they are going to show it again. Speaking of showing it again, this series love to reiterate by showing the same twice in basically 10 minutes apart from eachother.
Wrap-up
After lost is a mess of show that could benefit from better editing and maybe a rewrite or two but if you want to give a try, you're very much welcome to. Anyhow, thanks for reading.