YOU SAID:
Im a boy with a big fat head
INTO JAPANESE
でっかい頭の男の子です
BACK INTO ENGLISH
It's a boy with a big head
INTO JAPANESE
頭の大きい男の子です
BACK INTO ENGLISH
boy with big head
INTO JAPANESE
頭の大きい男の子
BACK INTO ENGLISH
boy with big head
That didn't even make that much sense in English.