...no? There's no indicator she's imaginary or false, just that the protagonist keeps a picture of her girlfriend as a wallpaper to motivate her when things get tough.
You're real nice too, Sakura.You agreed to move in with me,after our high school graduation.Of course I will, senpai...I appreciate that.I want you to be by side forever...Even if the rest of the world doesn't need me,I will try to live as best I can, as long as she wants me to.