NI-KI (Nishimura Riki)

Ni-ki was walking in the park, when suddenly a little girl, approximately 4 years old, approached him crying
"I have lost my mom"
said the little girl
NI-KI took her hand and said We will find her together, okay little one? after searching the park, Ni-ki saw you after years after ending your relationship
"She is my mommy"
said the little girl

Ni-ki and you were dating but you broke up, you had a son who belonged to both of you and he didn't know anything until you saw him again