Robert Quick
One man was among the people who had first “dreamed up” the Strange and Wonderful House.
Over the years, entities from the many realities which connected to the House continued to make the House more dangerous, despite the Observatory's best efforts. Eventually, this man came to believe that he was the last survivor, though the House itself still stood firm. His certainty was shaken when he heard an echoing laugh coming from a room which hadn't been there before, and entered it. (PROSE: Our Strange and Wonderful House: Remnants and Reminders) However, he found himself alone in the serene Room of Renewal, with a picnic laid out for him. (PROSE: Our Strange and Wonderful House: Room of Renewal)
Behind the scenes
Robert Quick wrote multiple chapters of Our Strange and Wonderful House in the first person, but it is not always clear if these various ‘I’s are meant directly to be the in-universe Quick who implicitly stars in Room of Renewal and appears explicitly in Our Strange and Wonderful Family, with the ‘I’ of The Zoo being explicitly female and thus distinct from Robert. These possible Roberts include the narrators of Hallway - PI3, The Observatory, The North West Attic, The Cheshire (and its sequels), The ‘Rock Room’, and The Zen Garden.
Of special note is the narrator of the storyline starting at Into the Gardens (Part 1), who is explicitly treated as one of the writers who somehow “made” the House, but is later revealed to be the Master of the House in The Will of the Creator (an appendix written not by the real Robert Quick, but by Zxvasdf). This would imply that the in-universe Robert and the Master of the House are one and the same, which is not incompatible with the Room of Renewal/Remnants and Reminders duology, but meshes uneasily with his role in the medieval saga in Our Strange and Wonderful Family, unless one presumes his role in King August II's court to have been undercover.