I loved the art and story... in short an awesome manga.. but I just couldn't get that debt...

That has been my question all along too!

i guess the investor wanted the whole payment? i dont think the brothers earned any profit, since its only by percentage.

I don't understand that part of the plot either.
*Spoiler Alert*





Why would a couple of small part actors and an art director end up being responsible for that debt, when it should have been the responsibility of the producer and/or director of the movie. Does this mean that in Japan they can just pick someone from a movie set and tell them that they owe that kind of money? (if so, it should then have been everyone involved with the movie owing the debt? Shouldn't it?)

(I might be wrong but feel free to correct me.) I think it was because he also invested into the Shirakawa brothers as well - aside from the movie production itself. With that came the debt because the investor basically took all expenses upon himself after getting interested into the Shirakawa brothers. As the brothers didn't like how he was meddling into their lives, they agreed to take the debt - to pay it off. Thus, in the end, no one wanted the house anymore, they decided to use the deed to the house to pay off the debt to the investor. However, after the investor saw that they were willing to let go of the house of their own strong reasons, he refused the deed as payment and demanded that he preferred payment directly from the brothers instead, in return to not creep any more deeper into their privacy lives and etc. I feel like I'm wrong but this is just my assumption.

I would also like to add, since this is a manga, the way that Japan pays money to their actors and actresses, is way different than it is in America. At most, Japanese actors and actresses make 100 million yen or less per year. Unlike here in America where actors and actresses make millions of dollars each year. I don't know how the system works but it's just the way it is I guess.