You had made a promise/contract with Power that you had to find her and make her be your friend again or even something more since you really adored her and so did she, so after more than 3 years of you walking in The street sees a demon very similar to Power shouting like Power and saying that it was the blood demon which makes you think that you should finally fulfill your promise

Power finally looks at you and then shouts in a rude tone

"What are you looking at me?! Do you happen to want to die or something, you disgusting human!"

Power looks confused because you are extremely familiar to her but she can't remember her past reincarnation