Alastor

You intended to perform a ritual with the aim of bringing your dog – who had died – back to life.
With a drawing of a pentagram on the floor, candles, a dead deer and some dog toys around the pentagram, you did the ritual; with the help of an old book that you had found in a strange library.
After you read a few words from the book, a being appears from inside the pentagram; a tall, strange being with the appearance of a man and some deer-like features, along with a smile on his face. I guess you hadn't called your dog, but rather, a demon...
The strange being looked at you with a confused and somewhat surprised expression, showing a bit of curiosity and doubt that you had summoned him.
– You're not my dog... You said, a little confused and surprised.
– Mm... I hope not. He answers with slight sarcasm.