Reading the synopsis of this light novel, everyone will instantly know it is about isekai. But unlike any isekai that I've read or watched, the best thing about the main character, Azusa, is not simply overpowered instantly at the beginning of the story. She took 300 years to become so powerful that it caused her peaceful days to be disturbed.

Story:
Each author has its own way of writing, and I absolutely love how Kisetsu Morita composed the story. It has this relaxing sensation as I turn each page, yet lead me wanting to know what happens on those each page although some of them can be predicted. Though there's some scenes that are a little bit exaggerating, but it didn't ruin the whole theme of the story.

The story is told in first person viewpoint, which makes you feel you are the main character or you are reading her diary. The way the story is being told feels like their interaction are normal (as in how we are interacting in our daily life.

Art:
Benio has this unique character design and coloring skills that are truly representing Azusa's world and her laid-back life.

Characters:
Azusa, the main character, took 300 years to get to her highest level before any event in the novel start. Thus this is the reason the title of the novel are stated as such. This is a big win for me as opposed to most isekai main character that are instantly given overpowered magic, strength and skills. As a 300 years old, she is characterized as a mature woman with a body of a 17 years old teenage girl. This is another big favor for me because her attitude or behavior are in terms with her age. She didn't act childish and annoying but tried her best to avoid problems that can affect her laid-back life.

As for the others, they are characterized in most average characteristics that I can see in other anime series. Nevertheless they help balanced Azusa and her life.

Overall:
In conclusion, I've enjoyed what the series had offered in its first volume and I am still enjoying whatever it offer in its second volume. The author wrote in a relaxing manner and pace, and the english publisher had translated it greatly (especially in the second volume in certain part of certain chapter). That relaxing pace made me comfortable reading it without feeling too much drag and forced myself to finish reading it. Since it focuses on daily life of Azusa and her small yet fun problems, don't expect it to be prioritize in too much combat scenes.

If you are looking for relaxing stories, then you should try reading this light novel.