Alice Sakaguchi is a shy and quiet high school student who has recently moved to Tokyo from a peaceful town in Hokkaido, a place she misses greatly for its lack of pollution and noise. At the outset of the story, she finds herself frequently teased and mocked by her young neighbor, Rin Kobayashi. Despite this antagonistic beginning, Alice is revealed to be a kind and deeply sensitive person, possessing an unusual and profound empathy for nature. She retains a special ability from her past life as the alien scientist Mokuren, allowing her to communicate with plants and make them grow simply by singing to them. This power is a vestige of her identity as a Kiches Sarjalian, a rare type of psychic blessed with gifts of growth, marked by four red dots on the forehead. In her previous existence, Mokuren was a beautiful biologist with long blonde hair who was beloved by her colleagues, but her current incarnation as Alice shares no physical resemblance to this former self.

Alice’s central internal conflict stems from her resistance to embracing her past life memories. She is terrified of losing her current identity as Alice, fearing that she will be completely subsumed by Mokuren's powerful memories and the overwhelming expectations others have of her. She feels she could never live up to the idealized version of Mokuren that her fellow reincarnates anticipate, leading her to actively avoid the dreams and meetings that would force her to remember. This fear is so strong that she decides to quit the group's after-school gatherings to join the school choir, causing even the other reincarnated individuals to doubt if she truly is Mokuren. Her motivation is not malice but a desperate need to preserve her own sense of self and autonomy, afraid that awakening would mean her present life would be erased.

Her role in the story is inextricably linked to the group of teenagers who share dreams of their lives as moon-base scientists observing Earth. She is considered the key to understanding the past, as she is believed to be the reincarnation of Mokuren, the biologist whose fate was tragically intertwined with the other scientists. Her most significant relationship is with Rin Kobayashi, the young boy who torments her. After a heated argument in which Alice slaps him and he falls from a balcony, Rin enters a coma and awakens with the full memories of Shion, Mokuren's tormentor from the past. Using the incident as blackmail, Rin forces an engagement between them, a situation Alice initially endures out of obligation. Over time, however, her feelings evolve from reluctant care for a neighbor to genuine affection, compelling her to look past their nine-year age difference. Her relationships with the other reincarnates, such as Jinpachi and Issei, are also crucial, as they represent both support and pressure for her to reclaim her past.

Alice’s development throughout the series is a gradual process of coming to terms with her dual identity. She moves from a state of complete denial and fear to a more courageous acceptance of the truth about her past life. She is pushed toward this awakening by Rin's relentless and sometimes forceful methods, including using a telepathic signal called a Synergetic Cascade to trigger her first moon dream. Eventually, she is forced to confront the painful and complex history of Mokuren, including the trauma of being raped by Shion and the complicated emotions that followed. This journey allows her to integrate these memories without losing her present self. In the sequel series, set fifteen years later, Alice has fully embraced her future, marrying Rin and becoming the mother of two children, a son named Ren and a daughter named Chimako. Her notable abilities, inherited from Mokuren, are her unique plant empathy and the power to accelerate plant growth through song, a direct manifestation of her Kiches Sarjalian heritage.