Mana (マナMana) is paired with Ayuta as one of the unlockable couples available after beating Story Mode with Escher and Musiea and/or Eluca and Zhamo. She is the princess of an Eastern country and was about to be betrothed before being taken to the Ark Arena.
In Ayuta's route, it turns out that Mana is actually one of Princess Mana's body doubles, and her real name is Shea (ヤエ Yae). She was supposed to keep the princess safe until her betrothal. She reveals her identity to Ayuta before the Arena battle against Olgar and Vahti. She is an outgoing person; she practices archery and horseback riding. The first time she meets Ayuta was when she falls from the horse she was riding and was rescued by Ayuta. Ayuta has feelings for Shea, and she, in return, also has feelings for Ayuta. She is secretly jealous because Ayuta still seems to have feelings for Theia, the original First Woman, whose consciousness has become the driving force behind the Ark 'In lieu of AI'. In the end, Ayuta chooses to live in Shea's world and Shea, in return, promises to Theia that if they ever have a daughter, it will be named after her. Theia gives them her blessing, and then finally dies after eons of time travel. It is unclear whether or not the Princess Manas in the other three timespaces are the true princess or still one of her body doubles, as Mana is always referred to as Mana in those storylines. However, each will inevitably die during the story. During the Qualia fight, it is Shea who appears beside Ayuta.