Yota's Picture Book Is the First Future That Is Not Built Around Moemi
SPOILER!
After Moemi and Takashi begin moving forward together, Yota pours himself into a picture-book project. It is a quiet development compared with Ai literally fading out of existence, but that is why it matters.
For most of the OVA, Yota reacts to other people's feelings. Helping Moemi, envying Takashi and worrying about Ai all define him in relation to somebody else. The project gives him something he is making because he wants to make it.
Why it matters
Yota begins to move forward before the finale tells him who he gets to be with. That keeps the ending from reducing his growth to 'he found a different girl.'
Debut: Ep 005 - Ai Disappears!
The Ending Chooses the Relationship They Actually Built
SPOILER!
The final episode strips away the original fantasy piece by piece. Yota enters
Video World Turns Yota's Emotional Avoidance Into an Obstacle Course, confronts images tied to Moemi and Takashi and keeps moving toward Ai even though Ai began as a product designed to soothe him.
That distinction is the entire ending. Yota is no longer choosing the perfect girl from the tape, and Ai is no longer simply performing the comfort she was made to provide. He is choosing the person created by all the messy time in between.
Why it matters
The OVA closes by treating a relationship with an artificial beginning as real because of what both people chose after the beginning stopped controlling them.
Debut: Ep 006 - Ai, Ai, Ai