Mitsugu Bamba is a high school girl who is crazy about donating her blood, to the point that she feels compelled to visit a local blood bank despite the unfriendly nurse. One day, Mitsugu encounters a beautiful girl there who looks like she has come from overseas. The girl is so pale that she appears ready to faint. Instead, she suddenly starts trashing the blood bank. The girl then loses consciousness and so Mitsugu takes her home.