Ishtar is the goddess of beauty, good harvests, war, lust, discord and fertility in Mesopotamian Mythology/Sumerian Mythology/Babylonian Mythology, one of the many Earth Mothers that inherited the power of all creation from the Goddess of Çatalhöyük's Potnia Theron in 6,000 BC.
...But now she's a Servant. One that's haughty, overconfident, and a bit grating to many people that first meet her.
But, well...She's stacked. You can forgive her, right? Plus, she's a goddess! That's gotta be worth something!