The third Date A Live Visual Novel.
Contains Examples of:
- Affectionate Nickname: Rio is fond of these. She refers to Shido and Rinne as "Papa" and "Mama" respectively, Maria as "Onee-san" and Kurumi as "Kurumin." Rio also refers to Marina as "Okaa-san" before disappearing in every route that isn't the true ending, signifying Marina's role as her Guardian and the new Ruler of Eden.
- Ascend to a Higher Plane of Existence: A straighter example happens to Marina again here, as she is reincarnated by Rio into an actual human in her Eden.
- Back from the Dead: During Rio Reincarnation, Rio resurrects Marina as her Guardian in the new Eden.
- Deadpan Snarker: Not as much as Marina, but Maria does have her sarcastic streak by the time of this visual novel. Again, this may be side effects of sharing her body with Marina.
- HeelFace Turn: We get to see the results of this trope with Marina, from Ars Install, on her in full in Rio Reincarnation.
- Ret-Gone: If Rio cannot find her "most important thing" to complete Eden in seven days, she will be Ret Goned, alongside Rinne (and, albeit without being forgotten, Marina as well). This happens in the true ending, Rinne's own route.
- Sharing a Body: Marina and Maria share a body in the new Eden during Rio Reincarnation. As a Call-Back to Ars Install, Maria is active during the day while Marina takes over during the night.
- Tsundere: In Rio Reincarnation, Marina is reduced to this whenever Shido is being particularly nice to her. Also toward Rio, as despite all she says about Eden being worthless, Marina still helps Rio to try and complete it anyway.
- Undying Loyalty: Marina shows this for the titular character. Marina ignores her own feelings and motivations if that means helping Rio, see the spoilered entry of Big Sister Instinct and O.O.C. Is Serious Business above.
- Your Days Are Numbered: No matter what, Rio will disappear in the seventh day of the new Eden. Either because Eden awakens fully and a new Ruler is chosen, which occurs in most endings, or because she cannot find "the most important thing" and thus unable to complete Eden in time, which occurs in the true ending. This only gets averted in Rinne's alternate route, after Rio's reincarnation into Shido and Rinne's daughter.