The TARDIS or to be nerdy the "Time And Relative Dimension In Space" is a time machine like space ship where the outside it looks like a old Police Box that were popular in late 19 century, but once you go inside you realize it's somehow bigger in the inside. It would have a futuristic aesthetic while somehow looking old as wine. It would seemingly have a conscious, with it sometimes making hums with itself and rarely taking control of its self in a desperate attempt or introducing itself to someone new. It would have once a proper owner but he forgot she existed and so she teleport to a random empty alleyway to get herself a new owner. It would go by feminine pronouns and she likes to be treated with care. She is able to travel through space and time to go somewhere in the past or the future, or simply go somewhere that takes hours to go to. Once inside you could see her main console with a tube in the middle to indicate she is in motion. The console has a bunch of buttons, levers, and anything that moves and does something. She would also have screens on the side to see where to go or interact with stuff on it, or text to talk to you.