Kei Toume: Lament of the Lamb: v. 4 [2004] paperback

Minase and Chizuna urge Kazuna to go back to school. Resuming a normal life may help gain greater control over his illness, they say. But, Kazuna adamantly refuses. Minase wonders if Yaegashi might be the reason for his unwillingness. Meanwhile, Yaegashi worries about Kazuna, she's upset that his attempts to avoid her. Kazuna's friend, Kinoshita, asks Yaegashi to take Kazuna's report card to him - that would be an excuse to see him. Kinoshita runs into Kazuna in the hallway. A student tries to befriend Chizuna, but Chizuna tells her she has no need for friends. Friends, thinks Chizuna, are just a burden when you've so much to keep to yourself. Meanwhile, torn between secrecy, and his need to confide in a friend, Kazuna decides not to divulge anything of his illness to Kinoshita. Kinoshita, vexed, leaves him. Eager and anxious to seek Kazuna out, Yaegashi goes to the Eda's place to deliver Kazuna's report card. But, she's greeted only by a reticent Aunt Natsuko. Natsuko does not divulge Kazuna's new address, afraid that Yaegashi will discover too much. She takes the report card off Yaegashi's hands, and says she'll give it to Kazuna next time she sees him.
Yaegashi, walking away, becomes deeply upset at being cut off from Kazuna, at the prospect of never seeing him again when she runs into Chizuna. Chizuna bluntly asks Yaegashi about his connection to Kazuna. She tells her to stay away from him, saying that Kazuna's disease makes him dangerous. Yaegashi pleads to help him, but Chizuna says that only she herself is capable of helping him. At home, Chizuna tells Kazuna that she's been dreaming a lot about Mother, a woman about whom she remembers very little. That night, Chizuna succumbs to her increasing weakness, a result of the medicine. Chizuna, gasping, tells Kazuna that she needs to feel needed by him; it's what keeps her going. She also tells him about her conversation with Yaegashi and prods him jealously about her. Suddenly, she grabs and kisses him. Despairing, Chizuna confesses to Kazuna that he is indeed her replacement for Father, that she is trying to assert control over him, emotionally and physically. Kazuna tells Chizuna that he'll never abandon her, the way their father did. Later, Minase tells Kazuna that the medicine that she takes to control her attacks could be the cause of her weakened state.
Minase says that Chizuna's longing for her father is so great that no one's else blood will satisfy her cravings should she suffer another attack; the medicine is her last defense against her vampiric illness taking a lethal turn. Minase explains the delicate and complex relationship Chizuna had with her father: she both loved and needed him to survive while, at the same time, resenting that it was only because of her resemblance to his dead wife that garnered Father's affection. Kazuna offers up his blood, saying that he reminds Chizuna of Father, but Minase rejects that solution. Her attachment to her father is too intense for Kazuna to intervene. Back at home, Kazuna reflects on his own helplessness and wonders if he doing any good by perpetuating his sister's father delusion. Chizuna comes to him and, in a tender, moonlit moment, they kiss again. At that instant, Kazuna doubles over, gripped by another attack. Chizuna offers her blood to him. Kazuna, instead, lunges at her ravenously.