I was sick of living in the human world. It's nothing but a vortex of greed and hate...Madeline
Madeline uses the same sprite as most young women NPCs in the game. She has long blonde hair held in a ponytail with a headband, and wears a red skirt with a white top.
Madeline was entirely disillusioned with humanity, feeling people are just greedy and hateful, and in her drive to get away from them she stumbled on the gate to the esper world. She was willing to obey the espers' will to remain in peace without humans, and only stayed on Maduin's urgings to challenge the preconception that the two species cannot co-exist. When the Esper Elder discussed his plan to permanently sealed the gate between worlds, Madeline barely hesitated before agreeing, claiming the other world held nothing for her anymore. She acts reckless and emotional at times, fleeing into a storm in her disgust over humanity, venturing into the esper world alone after Maduin took her in, and then attempting to flee their world with Terra when the other espers accused her of treachery.
Angry at the sins of the human world, Madeline went out into a terrible storm. She somehow found her way to the Cave to the Sealed Gate and crossed into the esper world, where she fell unconscious. Maduin, the guardian of the gate, brought her to their elder's home to rest. When Madeline awoke Maduin was smitten with her and gave her his pendant. The espers believed humans and espers could not co-exist, as humans had once exploited their powers to start the War of the Magi. Madeline agreed to return to the human world the next day, and Maduin took her back to his home.
While Maduin was asleep, Madeline snuck out and made her way to the gate. When Maduin caught up to her he offered her the option to stay, but Madeline questioned this, echoing the idea that humans and espers can't co-exist. The two conceived a child together, Terra, and Madeline remained in the esper world.
Two years later, the Gestahlian Empire found the portal to the esper world and Emperor Gestahl led an invasion to capture espers for experimentation. Madeline was taking refuge with other espers in the elder's home when he announced his plan to cast a spell to sweep Gestahl and his soldiers out of their world, and then permanently sealed the gate. The espers looked to Madeline as they announced this, but she claimed the human world had nothing for her. The elder left to begin his spell, and the other espers accused Madeline of being an ally of the Empire who had spied on them. As Maduin defended her, Madeline grabbed Terra and rushed to the gate.
Maduin followed her and found her collapsed before the gate as the elder's spell took effect. Madeline insisted she had nothing to do with the Empire and Maduin believed her. As he tried to help her back, Terra was flung from Madeline's arms by the force of the spell, and both she and Maduin followed. Outside the gate, Gestahl noticed her and took Terra from her, delighting in the prospect of a half-human, half-esper child. Madeline stood and tried to stop Gestahl from taking Terra, but he struck her and left.
It is not clear if Gestahl killed Madeline or merely knocked her down, but she is not seen outside of this flashback to Terra's birth and it is implicit that she is dead by the time the game begins.
Behind the scenes
Yoshinori Kitase has commented on Madeline and Maduin's story thusly: "Things didn't look particularly realistic in the Super Famicom era, so we were able to express things in all sorts of different ways. The Maduin and Madeline scene had a very short plot line in the scenario. But we got across the emotion that Mr. Sakaguchi wanted to convey, and really put everything we had into creating the cut-scenes."
Madeline is a variant of "Madeleine". Madeleine is a feminine given name. It is a form of Magdalene, well-known because of Saint Mary Magdalene. In the United States, this name often appears under the spelling Madeline. The name means "from Magdala", "tower", and/or "elevated, great, magnificent".
"Madonna" is from medieval Italian ma donna, meaning "my lady". It is a common name for the Virgin Mary, whose story Madeline's could be interpreted as paralleling.