Vergil from Devil May Cry is a half-human half-demon anti-hero who seeks to gain power. His life goal is to achieve the most powerful form of himself that he possibly can, even at the expense of others, so he can protect himself. Vergil was attacked by demons at a young age and survived but lost his twin brother and mother, which lead to his complex of never relying on others and gaining power through unethical ways. I would invite Vergil to my dinner party because his story fascinates me and I'd love to have a long conversation with him about his pursuit of power. He might not be the best dinner guest, but I think he could stand half an hour without teleporting away.
Gale from Baldur's Gate 3 is a human wizard that is a companion in a DND journey to Baldur's Gate. He is an extremely well-read person and very friendly to get along with. He enjoys reading, wine, and has a tressym named Tara. Gale was also at one point a chosen of Mystra, the goddess of magic. I would invite Gale to my dinner party because he's very sweet and easy to talk to. I think our combined interest in reading would be an invigorating conversation to have, and like Vergil, he also has an interest in seeking power.
Ruler James Moriarty from Fate Grand Order is a spin-off of a version of Sherlock's James Moriarty from the novels. James Moriarty is known to be a professor and the villian in the Sherlock Holmes novels. He is cunning and unmorally evil, but extremely smart due to his background as a professor. In this version, he is a younger version of his novel self back when he was a professor and villian, but just as morally gray of a character. I would invite Ruler James Moriarty to my dinner party because I find his character to be very interesting and I'd love to hear him ramble about his work. Also, much like the other guests to the dinner party, James Moriarty has a interest in gaining power.