I’m a little…confused. Are those the character’s hypothetical last words? Who is the ‘he’ and does his ‘fall’ correlate with their ‘end’? As a line of writing it’s by no means bad; you get a good gist of the character’s personality and idiolect, but personally I like something that sets the scene a little more before going into the deeper context, as a first line. Even if you’re beginning en media res, it would be more enticing to know something broader than the character’s first thoughts about a specific event that has not yet been revealed; maybe some thoughts about the situation they were in? You could elaborate more on their ‘end’.