Even though some people thought this story was a cliché, I still enjoyed it and I couldn't tell how it would end. Three endings were possible: 1. Kakeru would still die, 2. Kakeru would live happily ever after, or 3. Kakeru and Naho would start dating and Suwa would die. The teaching in these would be: 1. Everyone has regrets but you honestly couldn't have done anything to avoid it, 2. You can help others if you just pay attention to others, and 3. Happiness and unhappiness stays the same no matter what you do.

Other teachings that were there right from the beginning was, don't keep your trouble and regrets to yourself only, it'll wear you out. And, please don't commit suicide, it will only result in guilt, regrets and sadness in others, no matter if you weren't so close as you'd wanted to.