High school student Mizushima receives Valentines Day chocolates from the new student, Monami. Little did she know that the chocolates contained traces of Monami's vampire blood. He gets infected from eating them and Monami confesses that she wants to live with him forever as vampires. Meanwhile, Mizushima decides that he wants to fully become a vampire with Monami's help. Keiko, Mizushima's girl friend, sees the two on the school rooftop kissing and in a state of hysteria, attempts to throw Monami off the roof but falls off herself instead. Keiko dies but her father, Kenji Furano, the mad scientist, resurrects her as Franken girl. Thus begins a deadly combat between Franken Keiko and Vampire Monami in the name of love.
After a convenience store robbery, three unidentified men hold a group of people hostage in a hospital. Inspector Ishida and Captain Tohno handle the negotiations while one of their colleagues, Lt. Ando, tries to find out why the men decided to take the hospital hostage. Through flashbacks, relevant information is revealed to the audience. When the negotiations are finished, most things seem to be fine until they lose track of the criminals. Then, the story unveils from a different perspective, its roots in feelings of love and vengeance.