Using Japanese cell phone overseas is expensive!
It cost 155 yen to receive call per minute,
It cost much when you call outside the Philippines.
If you have a plan to stay over a month, I recommend that you get local cell phone because it’s much cheaper.
Though I brought my sim free phone (Xperia D2105) from Japan,
I did not try to buy prepaid sim, because My school gave us a pocket wifi.