Anteros was the brother of
Eros, the god of love. Anteros was known to punish those who
scorned love or simply didn't return the love of others.
Anteros was born so that Eros could grow up. Eros' mother, Aphrodite, didn't want her son to remain a child all his life; so she went to Themis for help. Themis informed her that Eros needed a brother in order fo him to mature. Aphrodite took the advice and got together with Ares to give birth to Anteros. Afterwards, Eros grew rapidly; just as Themis had predicted.