YOU SAID:
Batman ate my underwear
INTO JAPANESE
バットマンを食べた私の下着
BACK INTO ENGLISH
I had Batman underwear
INTO JAPANESE
バットマンの下着を持っていた
BACK INTO ENGLISH
Had the Batman underwear
INTO JAPANESE
バットマンの下着を持っていた
BACK INTO ENGLISH
Had the Batman underwear
That didn't even make that much sense in English.