How much do I need for a 5 month internship in Tokyo, Japan?

Question:

I'm aiming for € 9000 (includes internship fee) which is around ¥ 930700 or $12000.
Will this be enough? Rent will be around €700,- per month.

Of course I want to do some sightseeing and stuff. Let me know your thoughts.

Answer:

I think it's more than enough if you don't have to pay for rent.