Upon boarding the Titanic, many people go to their cabin first (to go there, click on its number under your name). There you can sleep and, depending on the type of your cabin and class, eat and drink, wash hands, and/or use the toilet and take a bath. Most of the cabins don't have the latter two, but there are bathrooms and lavatories around the ship.
Your cabin can be locked, so that only you and your friends can stay in it. There is an option to “kick out” an unwanted guest by right-clicking their name in the chatbox or the list and choosing it. Also note that when you lock the cabin, anything said in it doesn't show up in the global chat (the globe icon in the chat box), but becomes available in the
logs after the game, or in the
archives. Therefore, if you want to do some ERP (erotic role-play), keep this in mind. It is recommended to fade the scene to black before things get too graphic.