YOU SAID:
anata no haato ni nico nico nii
INTO JAPANESE
あなたのハートにニコニコに
BACK INTO ENGLISH
Smile to your heart
INTO JAPANESE
あなたの心に笑顔
BACK INTO ENGLISH
Smile on your heart
INTO JAPANESE
あなたの心に笑顔
BACK INTO ENGLISH
Smile on your heart
That didn't even make that much sense in English.