Sonja is one of the major characters in the game and is playable in Lynn's route and have her own extra route. 21 years prior to the beginning of the story, she was a Caelrig General serving Count Vlad alongside Roselia and Kane. During Emmerzail's invasion on Caelrig, she and Roselia was tasked to guard the Wallacus Mansion (Raddicus Mansion in present day) while Kane is tasked with guarding the northern shores from Fort Baltronn. She learned of Count Vlad's plan to sacrifice his own daughter, Lisa (Lynn's mother), to complete his "Weapon" for use against Emmerzail. She comforted Lady Lisa and promised to protect her. Then, at one night, she found Aldrinn wounded and unconcious in Wallacus Mansion gate and she took him to the Physician to treat his wounds. After Aldrinn awakes, he told her of what happened to his homeland, Eilrich, and that he is coming to warn Count Vlad of Emmerzail's plans but he was ambushed on the way. The next day, upon meeting Lord Henry, Lisa's husband, she learned that Lisa is missing and after searching the mansion, she found her in the Ritual Room and interrupted the sacrificial ritual commenced by Al'Grimm and escaped with the help of Aldrinn. Then, they traveled southward to Orsia Town to seek shelter and protection from Sonja's old friend and mentor, Father Brennard, not knowing that Emmerzail was following them. In Orsia, Aldrinn received training from Father Brennard and became a Paladin. Sonja, who is attracted to Aldrinn's personality, came into his room in the night and had sex with him and married him the next day. After their marriage, Roselia came to Orsia and informed them that Emmerzail had defeated Count Vlad and his army and is marching south towards Orsia to chase them. Despite Aldrinn's warning, she and Roselia advanced and clashed with Emmerzail's forces, where they met and fought General Kane, who has been tricked by Emmerzail to capture Sonja with the promise, he'll let both of them go if he captured Sonja first. After Kane's defeat, Emmerzail appeared and killed Kane and raped both Sonja and Roselia and turned them into his sex slaves. As a sex slave, she was constantly abused and humiliated by Emmerzail. After Aldrinn defeated Emmerzail and sealed him in Chapel Orsia, Aldrinn died and she escaped from Orsia region before the great tremor that tore Orsia region apart from the mainland and creating the Orsia Isle. Ever since she was free from Emmerzail, she became a Half Succubus and, like any other Half Succubi, became slutty and horny all the time. She eventually gave birth to Sera and entrusted her to Minstrel, knowing that she can't raise a child with her slutty behavior as a Half Succubus. She then left and live in the wilderness until Emmerzail possessed Sera after Dreadfilt captured her along with Alice, Lynn, and Jenna. She can feel the return of her former master and set out to investigate Orsia Isle and eventually met Lynn.