At the introduction, Sirius couldn’t do anything but smile, having a very good relationship with professor Mulligan and knowing full well that the likelihood of the professor passing was much lower than that of most of these students finishing their doctorate.<br/>He stepped away from the door and slightly more in front of the blackboard, just to make sure that everybody could see him.<br/>“Hello everyone,” he started, a pleasant smile on his face as he took them all in. He was surprised to find one face that wasn’t white among the four, which made him smile slightly wider to that guy than he had to the other three.<br/>“As professor Mulligan just stated, my name is Sirius Black and I am currently writing my dissertation on molecular gas and ionising radiation in star-forming galaxies,” Sirius explained, spending most of his days up to his eyes in his studies so he knew the phrase by heart.<br/>“You are always welcome to reach out to me if you have any questions or need any help.”