Anime couple in a dark room with a large window

1 man (demon lord, demon horns, black hair wearing tuxedo) and 1 woman (succubus, demon horns, pink hair, wearing tuxedo), he sit in throne and being hugged from behind by her, loving each other, detailed eyes, detailed face, detailed outfit, the background is dark old mansion, full body illustration, absurdres, highly detailed CG, Makoto Shinkai Class production