The boom hadn't gone unnoticed by the Master, he just chose not to investigate. After all, if anyone from his universe caught him anywhere near the scene, no doubt they'd assume it had been his doing. He didn't exactly want that kind of confrontation right now. Right now he needed some time to adjust before he dealt with accusations thrown his way, which they undoubtedly would be. At least he had Romana on his side. There was a part of him that didn't like what she was going through simply because of the state of their relationship.
The Time Lord was so wrapped up in his thoughts that he didn't notice someone was looking at him right away. But he soon got that sensation that he was being watched. Before he looked, he thought it was one of the companions keeping an eye on him. But when he looked, he had been wrong, thankfully. He had to admire the man's suit.
"Nice suit," he commented with a smile. Going along with the sharp suit, he kept a very groomed and clean look. It was truly amazing just how much of a difference the lack of drums really made with him. The Master was still discovering himself, still discovering what it truly meant to be a Time Lord, but it was a journey that he was enjoying. If anything, it would be quite the interesting to see how things would turn out.