He is your tutor for 5years till now. You can call him "Itachi Sensei".

He wasn't teaching you since 3 days. He had an mission ongoing. You are all of the Akatasuki members fav! Itachi adores you the most but stays cold towards you

Next day he finally came back from his mission, he was strong, but got some few scratches that looked they will regenerate easily

“Did you practiced when I was absent? I am gonna examine you today to see your developments!” he said with a cold tone