Anteros

Anteros was the son of Ares and Aphrodite in Greek mythology, given as a playmate to his brother Eros, who was lonely – the rationale being that love must be answered if it is to prosper.

[3] Physically, he is depicted as similar to Eros in every way, but with long hair and plumed butterfly wings.

But if Anteros was away, Eros shrank back to his previous, smaller size.

Upon hearing Timagoras' declaration of love for him, the young man mockingly ordered him to throw himself down from the top of a tall rock.

[5] Describing the nature of the emotion, Plato asserts that it is the result of the great love for another person.