YOU SAID:
to whisper in her ear, to never mention of it again
INTO JAPANESE
彼女の耳元でささやき、二度とそのことを言わないように
BACK INTO ENGLISH
Whisper in her ear and never say it again
INTO JAPANESE
彼女の耳元でささやいて、二度と言わないでください
BACK INTO ENGLISH
Whisper in her ear and never say it again
That didn't even make that much sense in English.