The main character of our story had a rough fate during the childhood such as loosing his family, his house and being all by himself since then. But he have lived and even managed to settle a nice and quiet life of a peasant. And just when he thought that everything will be fine from now on he happens to save a pretty lady from the river which gets him into wild hurricane of new exciting adventures!
"Callisto" is the name of your ship. Your spaceship to be more specific. Once a military you are now giving your own orders and go to your own adventures. You happened to gather an amazing crew which includes not only the talented specialists but also hot looking chicks (alien chicks as well!) so your travels around the galaxy are exciting in more than one meaning of this word.
Before joining Commander Shepard in his mission of saving the galaxy brave quarrian Tali was on the mission of her own - the Pilgrimage. She has visited a lot of places and meet a lot of creatures during her journey and some of her adventures she is never going to tell Shepard about. Why? Because she wants Commander to see her as technician and not as horny slut who has jumped on top of the biggest cocks of the galaxy. But we are not Commander Shepard so...