Hikaru, I think you know this better than anyone. Father is not the man who donated 1/2 your DNA. Father is the man that is there for you. That worries about you and takes care of you. The one that loves you, no matter what. Like me, you never really had that sort of father.

You love her. You care for her. You are her father until the day she personally tells you different. Even if Shouta comes to claim her back; in your heart, she's your little girl....or am I wrong?