@Akera93 @IRIGAMAGORI I once read a one shot where an alchemist was asked by the girl he liked to make a love potion for her, but it turned out that she wasn't intending on using it on the person she liked, but on herself to force herself to love the person she was betrothed to (in classic romance one shot fashion, she liked the alchemist back, and he realized this because his potion makes you forget the person you were originally in love with)
I haven't read the novel this is based on but I hope this is the reason the princess wants the potion, but since the princess is not part of the main couple this is probably not the case... but I'm willing to wait and see what happens