In Love Live, a character named Nico Yazawa constantly says her catchphrase:
Nico nico nii!
It seems like if her catchphrase is derived from her own name, at the first glance. Sometimes, it is extended to a longer line, as she would say, for example:
Nico-nico-nii~ Anata-no haato-ni Nico-nico-nii~ Egao todokeru Yazawa Nico-nico~ Nico-nii te-oboete, Love - Nico ♡
What does "nico nico nii" mean, exactly?