https://demonsanddemonolatry.com/demon-of-the-night-duke-haures-night-demon/
This guy made himself known, I've seen him wearing a black cloak and the an animal skull for a face but didn't understand who it was. I used to think it was a wendigo and ignored him.
For reasons I won't share here I did a proper summoning yesterday, using sandalwood incense and a copper coin for his associated metal while facing south. It so happened to be that yesterday was the last day in one of this preferred periods according to website above.
Connection was a little difficult, even after studying the sigil I was unsure about his nature, that was why I used more items than I would otherwise have done. It was a surprisingly strong experience, with a feeling of reality changing during the ritual.