Japan will by the bonds of the so-called “European Stability Mechanism”. (See http://www.bloomberg.com/news/2013-01-08/japan-to-buy-esm-bonds-using-forex-reserves-to-help-weaken-yen.htm )
The ESM is an 80 billion euro pool of capital that can be levered up to 700 billion euros by selling bonds. Supposedly, 200 billion has to be kept safe but that remains to be seen. The ESM is a mechanism to lend more money to insolvent governments whose problem is too much debt. These governments borrowed too much. Therefore someone lent them too much.
