Invoking the spirit of the harsh but just Vlad Tepes: if a girl is incapable of self-sacrifice for the sake of her beloved man, then she is a sinner who deserves to be impaled!
Banishing the vampire's spirit back to Hell: the mercy of non-lethal execution will be shown to both convicts. The stake for the girl will be arranged according to the principle of a culinary syringe: a viscous enema will be made through a thick dildo in the anus, stretching the colon to create a feeling of impaling. The guy will be tied to the cross. The crucifixion will last exactly as long as it takes to push the viscous contents (e.g. gallium melting at body temperature, or latex of the required density, or a combination) of the syringe-pole through the opening in the plug at the top of the stake under the weight of the girl. It will be an object lesson in morality for everyone, both the victims and the audience. The next time they are definitely sentenced to crucifixion, they will be more circumspect and merciful to each other, so they will be able to enjoy the pain and shame on the crosses many more times!