After reading Cappuccino, Rouge Noir was a manga talking about more serious problems than the first one. Or not?

In Rouge Noir I greatly enjoyed the way protagonist was talking about music. I don't remember how long ago I was reading a manga or book and noticed such a passion with which a protagonist was talking about music.
On the other hand, the story was weird somehow. A woman falls in love with a 14-year-old boy? Well, anything could happen, I guess, but love for life? After this 14-year-old rapes her?
Seriously, am I the only one who sees this as an unrealistic thing? It makes me confused whether I should take this manga seriously or just as a simple Saturday reading. Probably the second option as the plot seems to be undeveloped and the story itself appears quite often in josei mangas maybe as an opposition to usual shoujo stories where love is rather idealized. There is no particular idea which would inspire reader as well as there is no deeper meaning in the plot. Reading Rouge Noir was something similar to reading Twilight - unrealistic plot, but the story itself was quite fun to read. It didn't make me think deep which is kind of cool if you don't get into reading such stories in an overly vigorous way.

This manga was rather good until I understood that the protagonist is pathetically in love with her raper. Later on I decided that this manga is not worth taking seriously and is made to bring enjoyment and fun on lonely evenings. The ending proved my opinion. This reading must be taken with joy. Without any commitments. Just like jazz, huh.