Undoubtedly the best back-to-school types of manga I've read so far. The story starts off with our main character at the age of around 30 (27) and is unemployed. At this time of age, people are usually out of their half baby- half adult stage and begin to become acceptance to or against reality.

Plot and character wise,
The story has a plot that starts up slow but is able to ease the viewers into a suspenseful friendship heavy plot line; in which, the characters not only discover themselves but also what is important around them. Overall, it teachers the target audience (I assume those around my age - highschoolers) to appreciate what youth and young love is left within them.
The 2 main characters, in complete contrast with each other as if to show juxtaposition of different ways of life in school and its pros and cons. Smart, school centered, and with no friends, Chizuru has always been focused in school and that makes her life somewhat miserable. We see that because of this, majority of those who follow her path IRL, lose the ability to socialize normally.
Reliving his life, Arata becomes a carefree man only to discovers and conquer his insecurities and overall becomes a better and more understanding person.
Basically, the plot was great and character development really is something else.

My personal feelings.
As a 17 years old, I feel that this series really speaks to me in a deep level. The reoccurring theme of regret has played a major role in my feelings in the story. Regretting not confessing to that person, regretting not taking the next step, and most of all regretting not enjoying your youth and high school years like everyone else. It has taught me to be able to look further than seeing school as a torture chamber but rather a machine of memory creation. All the friends to make, all the memories to create, and all the things to learn both socially and educationally. And for those older, it is a good way to reminiscence those school years you've left behind. Good memories.