Jean was first seen in Claymore Volume 8. She and her team were sent to eradicate Yoma from an abadoned castle. But when they arrived they were captured by Riful and Dauf. While Clare was roaming the city looking for Raki, she then heard the townspeople scream in horror. Seeing it was a member of the Claymore team she saw earlier. Her name was Rakel and she was severly wounded and missing a quarter of her body. She told Clare they were ambushed by an awakened being she manged to escape (but was most likely used to lure more Claymores). Hearing this Clare asked the townspeople to bury her and rushed to save the others. Jean and the remaining members of the team were being tourtured to awaken by Dauf stabbing them with his rods. Her friend Katea was starting to awaken and Riful told Dauf to see if she is strong. After they were both finished awakening Dauf striked first, and Katea striked back. But Dauf was too strong and he told Riful she sucks. So Dauf brutally bashed her into the ground. Jean was the only one left they were about to attack her but they sensed Clare entering the castle. After a while Jean awakened and Clare came to rescue her. Jean asked Clare to finish her off but Clare refused and helped her revert back. Clare then told her what she did to bring her back to normal. After the conversation Jean vowed her lfie to Clare and went to attack Dauf and Riful.
When finally reaching Galatea they found out who the two of the awakened ones were and why there were luring Claymores. Hearing this Jean started to attack Dauf but was unsuccesful. She devised a plan to attack him by using Jean Drill attack on his neck. They kept on missing only able to hit his hands. But after Clare got his attention she moved out of the way for Jean to finish him off. But when they were going to give the finishing blow Riful stopped them and left wtih Dauf. After there ordeal Jean continued to follow Clare because of her vow. But Rafael came out of nowhere asking which one is Clare. Then Rubel appeared and told them of there next job. They headed towards the north to stop Isley's army from reaching the south. Every Claymore was given a team but Jean continued to watch over Clare. She even met here friends and told them what happened between them. But while they were talking Isley sent there of his soldiers to see the Claymores strength. But each one were defeated. After their victory Jean followed Clare when Flora asked to talk to her. But again more of Isleys army arrived to attack. Then all of a sudden the awakened ones left the city due to Rigardo coming to finish them all off. He first searched out all of the strong ones then killed them mercifully. Jean survived his attack and was just injured. See this Clare became enraged and tried to attack him but he just kept on blowing her out of the way until Clare awakend her legs and was keeping up with him. FInally Clare awakend 50% of her body and Diced Rigardo into pieces as he died he said Beautiful (Due to the fight). Clare began to fully awaken and she was starting to lose her mind so she asked Helen to kill her but Jean came in and sacrifcied her life to revert back to normal.
Jean had the unique ability to twist her arm and use her sword as a drill. This was a useful technigue to pierce an awaken ones armor.