Lapshia is a magician with unknown motivations.

He carries a pair of bells tied to one of his fingers, which ring when he casts complex magic; for some reason Celica and Ekria are able to hear this sound, regardless of their location.

At the beginning of Battle Goddess 2, he has begun to awaken the Seven Elder Demons from their imprisonment, beginning with Elteno. She is openly contemptuous of him, but acknowledges his usefulness when she sees the powerful familiars he commands, and accepts his help in freeing Lanjerie. For his part, Lapshia bears the abuse with a patient, almost obsequious demeanor, and once Lanjerie has awakened, he convinces her to keep him in their service. Amused, she agrees, to Elteno's shock.

As the Seven are freed and begin their campaign against the nations of the modern world, Lapshia tells Lanjerie that his greatest wish is to remain by her side and see her wishes made reality. Softened by his behavior towards her, the goddess starts to fall in love with the young magician, and the two enter a physical relationship. When Empress and Io become aware of this growing attachment, both seem to disapprove, though neither one voices her opinion.

As the war proceeds, Lapshia tends to remain aboard the captured Melchian battleship [i]Illustrious[/i] while Lanjerie sees to her business elsewhere. Eventually Celica and his companions mount a counterattack, calling a meteor from the heavens to shoot the ship down. Through Lapshia's quick thinking, a crash is prevented, and the ship is grown into the trunk of a giant tree above the Cadora Mines. This has the seemingly unintended side effect of allowing Celica direct access to the ship, and he moves to strike at Lavine, the goddess who powers the [i]Illustrious'[/i] core. Rhea interrupts, but after she is bested by the heroes, Lapshia arrives and meets with Celica face-to-face for the first time.

He seems to know Celica already, addressing him by name, and feigning surprise that the Godslayer has "forgotten" him. He reveals that Celica is his true objective, though his reasons are unknown; the heroes find that they are unable to defeat him in combat. The childlike Leciente interrupts before he can deliver the coup de grace; to prevent Lapshia from killing her, Rhea tackles him and begs Celica to protect her. She then discharges all of her energy in an attempt to destroy the magician, killing herself in the process.

The explosion scatters Celica's companions, but Celica himself is captured and imprisoned within what appears to be a living tree. Over the coming months, Lapshia drains Celica of his lifeforce; Io appears to be assisting him, but is in fact enduring his abuse while watching over Celica. Lapshia seems not to care that Io is also replenishing Celica's energy whenever possible, and actually leaves the two of them alone when he travels to Celica's mansion and kidnaps one of the maids (either Suri or Ekria, depending upon the player's route.) He brings the captured maid to a cabin snowbound in the mountains, proceeds to rape her, and then leaves her there.

Meanwhile, the remaining companions rescue Celica from his captivity. During the long months of his recovery, the captured maid gives birth to a child; when Lapshia comes to check on her, he seems pleased, cryptically referring to the child as belonging to the maid, Celica, and himself. Elsewhere, Io and Empress confer, and Io confirms the magician's true nature.

Lapshia visits Lanjerie at her sanctum for the first time since the destruction of the [i]Illustrious[/i]. The goddess is overjoyed to see him alive, but the joy turns to horror when Empress arrives and reveals the extent of his betrayal. Lapshia makes no attempt to deny that he never felt anything for Lanjerie, and had simply been using the Seven from the beginning. Unable to bring herself to kill him, Lanjerie has him imprisoned (which he accepts without complaint); then, in a fury, she orders a final campaign of destruction upon the entire world of humanity.

Once Celica recovers his strength, he proceeds to engage and defeat each of the remaining Seven, leaving only Lanjerie. When he encounters Io and Empress, both seem to know Lapshia's true identity, but say that it's something best learned from the magician directly. Sensing that his time has come, Lapshia escapes from prison (telling a shocked Lanjerie that he could have done so at any time) and travels to Cuito Village, the snowbound mountain town where he left the kidnapped maid. Claiming the infant for himself, he leaves, shortly before Celica arrives to rescue his lost apostle.

Celica and his companions invade Lanjerie's sanctum and eventually triumph over her; however, refusing to admit defeat, she flees somewhere further within. There she meets Lapshia. In desperation she begs him to run away with her to someplace where the heroes will never follow. Coldly, he tells her that only one of them will be leaving. He then proceeds to rape Lanjerie, draining her of nearly all her lifeforce. Leaving her to die, he opens a portal to the Promised Land, an astral plane seemingly constructed from his own will.

Pursuing him into the Promised Land, Celica discovers a series of murals. They tell the story of how, long ago, a young disciple of Barouhart fell in love with a woman with long red hair. She soon fell under suspicion by the temple priests, forcing her to flee and leave her lover behind; in her absence, the priests brainwashed him and turned him against her, eventually arming him with a magical sword and sending him to take her life. Revealing herself to be the goddess Astraea, she won their battle. Rather than let the young man die, she gave him her own body so that he might live. Celica recognizes this as the long-forgotten story of his own past, and comes to realize the truth: that Lapshia is, in fact, Celica himself - or more accurately, the parts that were left behind when Celica merged with Astraea's body.

Lapshia rages at Celica, accusing him of having stolen the future that was rightfully his. They fight, and at last Celica is able to overcome him. Vowing that the fight hasn't ended yet, Lapshia produces the infant from Cuito Village; merging with it, he turns into an angelic demigod. It takes all the strength the companions have to defeat it, finally destroying Lapshia for good.

As a result of his nature, Lapshia is the opposite of Celica in many ways. Celica specializes in swordwork, while Lapshia's magic is exceptional. Celica is stoic and reserved; Lapshia, vengeful and prone to outbursts of rage when thwarted. Celica is almost comically dense when it comes to the minds of others, while Lapshia excels at manipulating those around him.