It has no overarching plot because it is a slice of life. What initially turned me off was that it featured activities usually done by old people, which is something I don't look forward to. Another source of consternation is the fact that it's not one scenario per episode. It's a series of chapters/skits slapped together to make one episode. If this were presented as a series of 5-minute episodes, it would have been more palatable.
But once I accepted this, it became better. It felt like the second half of the show was better, though it still felt like a torture watch.
The reason why it has a relatively high rating is because of grandma and grandpa's sweetness and chemistry. I cannot deny that. Because of them, somehow, I miss my grandparents (RIP).
This anime can be useful as a meditation for loving someone for life and maintaining that love through thick and thin. Also, it's a fine meditation on the inevitability of us growing old.
Unfortunately, the format did not click with me but YMMV. The technical aspect of the animation is fairly acceptable.
