Spring break is the time between second and third years of high school. Koyomi Araragi encounters a blood-curdling beauty. She called herself Kiss-shot Acerola-orion Heart-under-blade, an iron-blooded, hot-blooded, and cold-blooded vampire. Kiss-shot, who lost her limbs and was on the verge of death, asks Koyomi for help. After all her fear, confusion, and conflict, Koyomi gives her own blood to save her - and the next time she wakes up, Koyomi is Kiss-shot's kin. . Koyomi wishes to change back from being a vampire to a human. But for that to happen, Kiss-shot needed to fully regain her powers. With Meme Oshino, who acts as her negotiator, standing between them, Koyomi takes on three vampire extermination experts in order to retrieve her lost limbs. The last, hellish spring break of my high school life had only just begun.

高校二年生と三年生の狭間である春休み。阿良々木暦は、血も凍るような美女と遭遇する。彼女は自らを、鉄血にして熱血にして冷血の吸血鬼、キスショット・アセロラオリオン・ハートアンダーブレードと名乗った。四肢を失い死に瀕していたキスショットは、暦に助けを求める。恐怖と混乱、そして葛藤の末に、暦は彼女を救うため自らの血を与え──そして次に目が覚めたとき、暦はキスショットの眷属となっていた。暦は吸血鬼から人間に戻りたいと望む。だが、そのためにはキスショットが力を完全に取り戻す必要があった。交渉人をつとめる忍野メメが間に立ち、暦は失われた彼女の四肢を奪い返すべく、吸血鬼退治の専門家三人に挑むことになる。高校生活最後の、地獄のような春休みは、このときまだ始まったばかり──

Durante as férias da primavera, Koyomi Araragi encontra uma beleza de gelar o sangue. Ela autointitula-se de Kiss-shot Acerola-Oríon Heart-under-blade, uma vampira de sangue de ferro, de sangue quente e de sangue-frio. Kiss-shot, que perdeu os quatro membros e encontrava-se à beira da morte e pede ajuda a Koyomi. Depois de muita reflexão, Koyomi dá-lhe sangue para poder salvá-la - e quando Koyomi acorda torna-se vassalo de Kiss-shot. Koyomi deseja voltar a ser um humano em vez de ser um vampiro. Porém, para fazer isso, Kiss-shot precisava recuperar totalmente os seus poderes. Meme Oshino, atua como negociador entre eles.

Koyomi enfrenta três especialistas em extermínio de vampiros para poder recuperar os membros de Kiss-shot. As infernais férias de primavera da sua vida estavam apenas a começar...