Wayward pines are extremely awesome rooms if it's cool outside. As are natural caves.
For a man-made room... hmmm. Room circular with several alcoves into the wall. Thick shag carpeting, black, along with the domed ceiling. Wall covered with dark vines and Ivy (can be fake), though it stops at the tops of the alcoves. In one alcove a full size bed, fitting against the far wall and inner walls with ceiling 4 feet above the bedding. Fireplace in the center of the room, about the size of a small campfire, burning with maple wood, smoke ventilated with silent fan above a hole in the domed ceiling. Fish tank with light blue back lighting built into one wall, about 5x3x2, filled with lionfish and anemone's. Another alcove, opposite fish tank contains computer, desk, and full gaming station, cables hidden in the wall on the alcove. The entrace door is right next to the fish tank, opens outward. Vines and Ivy hang down over the door, have to walk through them to get in or out. Scented Candles are in small 10"x5"x5" alcoves spaced around the wall. Wall and door are of course sound proof. Speakers are hidden behind the candles, hooked to the computer. Large leather rotating recliner between bed and door, normally facing fire, two larger candle alcoves behind it for optimal reading lighting. Entire room about 30 feet across. 10 feet up, the dome begins, the dome is 6 feet at apex. A metal mesh platform runs at the 10 feet height, hole in the center. The mesh is designed to look similar to vines, capable of holding up to 1000 pounds so such things as people, hammocks or whatever can be hung from/placed on top of it.
Hmm, now I have a room goal to get tons of money for purchasing and constructing.
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I am Jon Stewart with some Colbert cynicism, Thomas Edison's curiousity, wrapped around a hardcore gamer sprinkled very liberally with Deadpool, and finished off with an almost Poison Ivy-esque love/hate relationship with humanity flourish.