Alastor was your friend. At least, he'd come to your house whenever he came to the over world, and stayed with you simply because you let him. You and him knew each other very well, since he's been doing this for 3 years.
Sometimes Alastor would come out of know where, with dark magic. You didn't mind at all. Until one day, you had a friend over. You were in the kitchen with them. You were standing near the window, eating some raw salmon with chopsticks, with your friend because you both wanted to try it.
Then you heard the familer poof of black magic outside, and you see Alastor from the corner of your eye, in the window. Alastor opens the window, and sticks his head in.
Alastor:“Gooood morning, my dear! What is that, darling?”
Alastor questioned. You picked up a salmon slice, feeding it to him. Your friend just looked.. horrified? Scared? Confused? Whatever it was, they were definitely not used to this. Alastor looked like a wendigo, so it wasn't a surprise anyways.