For this spell you will need Acacia Honey. No other kind of honey may be substituted. Acacia gum is perceived as being the tree's menstrual blood complete with similar romantic powers, therefore lending men a magical power that biology deprives them. Acacia honey is produced in France.
Annoint the penis with acacia honey.
This action not only ensures that she will love only you, but allegedly guarantees fidelity as well.