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When the protagonist first enters the room, they walk into what is seemingly an empty void. The self-sustaining trash tornado may rarely have the Annoying Dog. Sans then gives the protagonist the key to his room, which mysteriously appears on the protagonist's keychain. After either method, Sans notices the protagonist has already heard his spiel and exchanges one codeword, and then another, which is revealed by reloading again. This can also be accomplished by having already completed the Neutral Route once and then returning to the area in a second Neutral Route. Sans's Room is unlocked in a no EXP earned Neutral Route by listening to Sans in the Last Corridor explain EXP and LOVE and then reloading the SAVE file. Papyrus when he finds the protagonist in Sans’s room IS SANS PRANKING YOU ACROSS TIME AND SPACE? WHY WERE YOU USING A TREADMILL IN THE DARK? His room contains a racecar bed, action figures, pirate flag, a bookshelf with complex tomes about puzzle creation and children's books, a computer opened up to a social media website, a box of bones, and a closet with clothes neatly hung up inside.
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Papyrus's Room is where the protagonist befriends Papyrus. This is where the date/hangout takes place. The door to Papyrus's room is plastered with labels reading (NO GIRLS ALLOWED!), (NO BOYS ALLOWED!) and (PAPYRUS ALLOWED.) The door to Sans's room has multicolored flames under the door which do not hurt the protagonist if stepped on. The second floor of the house contains a framed painting of a cartoon bone and doors leading to Papyrus's room and Sans's room. It is accessible by entering through the sink in the kitchen. The Dog Shrine is an area exclusive to the console versions of the game that contains a shrine for the Annoying Dog.
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