Well, I'm sorry I haven't hung up the, uh, 'Hang in there, kitty' poster yet, Dean. Feel free to redecorate.
Inside Sam's Bedroom
Sam's bedroom is located in Room 21 in the Men of Letters Bunker. Sam initially feels that the Bunker is a place of work, and not a home as a reason to why he has not decorated it. He explains to Dean that he never had what Dean had with their parents. "I don't have any memories of home and whenever I've tried to make a home of my own it really hasn't ended well."
While Sam's room has no decorations, the shelves are lined with files and books for research. Sam has also installed a large TV and DVD player.
People who have been in Sam's room:
After knocking over a mysterious bottle in the process of trying to fix the computer, Dean calls on Charlie for her expertise in decoding the ancient machine. Charlie reveals that she has experimented with hunting on her own, but finds the experience less magical and filled with fantasy than she’d prefer. While the group watches Game of Thrones and awaits the files to transfer to Charlie’s Microsoft Surface Pro, Dean notes how Sam has yet to come to consider the base a home, and the mysterious bottle downstairs uncorks itself and begins forming a webbing on the wall behind it.
Sam is sleeping in his room when Dean wakes him up with loud music on his cell phone. Sam jumps up, gun in hand, and questions Dean. Dean claims to not be tired and says they have work to do. As Dean packs up weapons in the library, Sam joins him.
As Sam is sleeping in his room, he hears Dean screaming out his name in his sleep. Sam rushes to Dean's room with his gun and discovers Dean having an intense nightmare caused by the Mark of Cain. The next morning Dean asks Sam if there are any cases available. Sam tells him that there is one but that another hunter named Rudy is handling it. Sam then tells Dean that he is going off to watch a French movie being aired at some theater and that Dean is welcome to join him, which Dean refuses. He also tells Dean to stay out of his room.
After Sam has left, Dean, being the good brother that he is, goes into Sam's room and proceeds to prank him in various ways including rubbing Sam's toothbrush under his armpit, farting on his pillow, and taping down the rotary phone so it won't stop ringing when the receiver is picked up. In his room, Sam pulls out a letter from Bobby that Castiel handed to him earlier. In his letter, Bobby advises Sam not to go behind Dean’s back, because there might be one hell of a price. But he also says he knows that Sam will make the right choice, because he’s a good man and Bobby’s proud of him. Sam is moved to tears.
In Fall River, Massachusetts, Sam and Dean continue investigating their previous case, trying to find more soulless people in order to track down Amara. As they bemoan their lack of leads. Dean asserts finding her victims to be the best lead they have, but Sam counters, mentioning it's time to take Castiel off the bench. After discussion, Dean agrees and places a call to Cas, who tells Dean he has found no new leads from angel radio or any new info on Metatron while he has been holed up in the Bunker, bingeing on daytime TV talk shows. Dean chastises him for switching from quality TV like The Wire or Game of Thrones and encourages Cas to turn off the TV altogether and get outside for a bit.
At the Bunker, Castiel puts on his jacket and approaches the Bunker door, but has a flashback of trying to kill Dean before Rowena removed the spell, his torture by the angels responsible for Hannah’s death, his attempt to kill Crowley, and even his fight with Dean at the Bunker as Dean succumbed to the Mark of Cain. The flashbacks force Castiel to return to Sam's bedroom and continue watching TV.
As Cas continues watching daytime TV, the news plays a clip of a murder, shot by a witness on scene. Cas catches a reflection in the side mirror of a vehicle and is overwhelmed as he realizes Metatron is the cameraman.
Lucifer started to seek solitude in Sam's bedroom while playing very loud music. Sam pounds on the door and remarks that he has to come out sometime and talk to God, but he turned down the music and responded by stating that if God had something to say, he would hear it from him, and he turned up the music again after stating that he will be in his room until then. Dean tried to remind Lucifer that it was not his room. Sam stated that it was "my room" and continued to pound on the door.
- A Closer Look At Sam's Bedroom by karen on The Winchester Family Business site