Location from Sailor Moon by Naoko Takeuchi / Toei Animation
The gate between all timelines, guarded by Sailor Pluto alone — a liminal space outside of time that connects every possible past to every possible future.
The Door of Space and Time is the most important location in the series that almost no one ever visits. Setsuna guards it alone. She has been alone here for centuries. The three prohibitions — no time travel, no stopping time, no leaving her post — define her existence more than anything else about her. She has broken all three over the course of the series, each time for reasons that couldn't be argued with, each time paying a cost. When Chibiusa first found her here, she was the only person who had come to visit in a very long time.
A massive ornate door standing in a void, surrounded by nothing. Eternal in the literal sense — there is no day, no night, no changing light. The Garnet Orb above Setsuna's staff glows red in the dark. The door itself is always locked unless she opens it.