MEMORIES ～記憶のすべてを…～

In the facility called “Farm” main character is allowed by his father to have one girl who he calls La Nina. Girl's actual name is Make. She is a cheerful girl who very soon becomes protagonist's friend and then lover. But when he tries to ask her about the meaning of "La Nina" name, she suddenly falls in the state of shock and only whispers about her "fate".

[From vndbreview]