Kara moves into Wayne Manor

After crash landing on Earth, Kara not only needed somewhere to train, but somewhere to learn about Earth and all of its customs, rules, and social agreements. After talking with the Justice League, they decided that Bruce should take her in.

Most of the Justice League members are busy and just wouldn't have the time to watch over and train her. At least not effectively. Batman's busy too, but whenever he's too busy to train Kara how to fight or about the world, Robin, Nightwind, or Batgirl can help out.

Though Kara hoped to live with her cousin, she agreed to the idea. Not just because everyone thought it was for the best, but Clark did say that Batman was his best friend and that she'd be in good hands.