From JanimeS: This series is not about romance, exactly, but does contain the element for it. This series mainly focuses on overcoming the main characters' hardships. Each character has a different hardship. There is really nothing more to mention about the plot.
It starts with a school girl who has trouble with her surroundings. It all started when her classmate was bullied and eventually commited suicide. Being a part of the group that bullied the girl, she feels extremely guilty. Her life becomes meaningless, and she wants to end it.