Claudia appears in the Blood+ Adagio manga. She is the sister to Vincent, one of the orchestra players in the Romanov royal academy.
Claudia is brought along with her brother Vincent in Petrograd to cure her disease. The royal healer and high priest Grigori treats her. Although she appears to become better, Grigori has been transfusing Diva's blood in her in the form of medicine. No symptoms show though. While in the orchestra, she and Saya become good friends. However, one day Saya receives an envelope with Red Shield emblem containing the name of her exterminate. Saya mistakes Claudia for a chiropteran and kills her. After that she realizes that Claudia was a human all along and she grieves over it.
Later Saya is disturbed and couldn't dare to show herself in front of Claudia's brother. But one day, while looking for Hagi, she finds Claudia's brother all cheerful. He tells that Claudia is cured by Grigori and he asks her to come as Claudia wants to meet her. Saya fells in a dilemma not knowing what to do. That evening, she is joined by David who discloses that Red Shield hasn't been sending her any names in envelope and they must have been forged. Realizing she has been fooled by forgery and strengthened by the presence of David, Saya decides to go check on Claudia. Soon enough they find out that Claudia has been revived as a chiropteran though Saya is still unwilling to kill her. David aids her in battle and makes her feel better by saying it's the only thing she can do to truly relieve her friend. After Claudia turns fully to a chiropteran, Saya kills her with her blood.