I use Bigen oriental black from Sally's. It is VERY black and dark. I don't know how black she wants her hair, but Bigen will be very, very dark. I love it and it looks good on me, but not everyone likes jet black hair. She can try Clairol demi-permanent it works well, but it's not black enough for me. I also know quite a few people that use Wella demi-permanent from Sally's.