This may drive people away due to the incestuous title. Trust me it is anything but. This is the story of the girl and the boy from different families bonded by the marriage of their parents.
Unfortunately, both of their parents die shortly after. The rest of the story is about how the two kids support each-other through the years. Revealing any more about the story might be spoiling it so I'll end here with some vague words.
The plot has the pacing of a coming-of-age story but surprisingly has the thrill level of a slice-of-life. Give it a shot and it might just captivate you.