In episode 8 of Dance in the Vampire Bund, “Near Dark” (ニア ダーク), a kid named Yuzuru is watching late night television where some of the guests from episode 1‘s variety show appear. One of them also happens to be the woman who was bitten by the rogue vampire, who thought the feeling of being bitten was orgasmic but is fine now thanks to the vaccine. This is when Shinonome Nanami shows up as a vampire, thirsting for the one boy whom she desires above all others, but she barely manages to control herself before running away.
This leads Yuzuru to approach the Bund in search of his big sister Nanami (not by blood, but a neighbor), which leads to an attack by a self-destructing vampire that is defeated by Veratos, which leads to the discovery of school students turned vampire that have gone missing. These are students that have been vampires long enough that the vaccine has no effect so that they were supposed to be temporarily sent to a medical facility before presumably settling into the Bund, but they never showed up. Among the students is also Nanami. Considering that a big point of the Bund is to be a public haven where vampires could live in exchange for no vampires roaming indiscriminately outside, this is a huge problem, not to mention the organization that must be behind this.
Meanwhile, Mina rudely reading a novel that Yuki is writing in her notebook leads to the two becoming friends. The two can emphasize with each other as they both love or loved Akira (it helps that Yuki is no longer actively pursuing him), and Mina also apologizes for having stolen the ring Yuki gave Akira (turns out it really was Yuki who gave him the ring). Seeing how Mina and Yuki being able to understand how each other feels and become friends makes Veratos and Akira feel glad, especially since Mina has no really close friends unrelated to romance or hierarchy.
As for Nanami, it turns out that she’s now a thrall of a certain rogue vampire, who also happens to be an old adversarial acquaintance of Veratos. This is revealed when Mina personally seeks out Nanami to help her, given how Nanami at least is trying to control herself. The same can’t be said about the horde of mindless vampires that show up, and Mina has no compunction about setting her royal guard upon them, turning around an ambush into an ambush of her own.
However, the adversary makes her escape with Nanami in tow using more self-destructing vampires, which means that we’ll be seeing more of the full-of-herself vampire.