Jonah seemed to know a thing or two about positioning, but this was murder, and Shin lived and breathed it. So many people are unaware of how much of an assassin Shin actually is, and to think he could not move silently and quickly was a fool's folly. Though admittedly his footwear was not so perfectly designed for this task, so he would need to improvise. More likely he was to be spotted before he was heard, Shin's mobility was not in question. After getting onto the rooftop he ran to the edge and caught a glimpse of Jonah retreating down the alley. 

Lowering himself to the rooftop, pressing the tips of his fingers against the roofing tile. For a single second he flexed his feet and pushed the leather toe hard against the roof. There was a slight creak, and a snap. By leverage and force he had pushed his feet through the soles of his shoes. The soles of his shoes fell off and onto the rooftop, their weight made the noise they made very subtle. Now he could move silently, he stood slightly and kept his head low before beginning a quick dash across the rooftops. Every footfall was halted just before his toe hit the roof, landing on the ball of his foot and pushing ahead before his heel could follow. 

In the time he'd spent to remove the soles from his shoes, he'd managed to lose track of Jonah in the moment. Perhaps stealth wasn't the best tool for this job, but he was an assassin. Finding and killing people was literally what he was paid for, if he couldn't find an old man brandishing a pair of magic guns in a Western American town, what was he even getting paid for?

Wait.

He wasn't getting paid for this at all.

This was a private excursion.

"Shit." He muttered silently as he ran across rooftop after rooftop, demonstrating some particularly impressive agility as he dropped down to look through the various windows. Leaping back and forth from rooftop to ground to peek into different windows, traveling in the vague direction that he had seen Jonah run previously, hoping to catch a glimpse of his target or hear the jingle jangle of his spurs. Strangely enough, he hadn't noticed yet, but Shin himself had been leaving a trail of blood behind himself. His arm was still bleeding pretty decently.