What I am more curious than death looming over.
But the whole order of things as they should be. Didn't the school prez changed the order by killing his teacher in the past. She didn't die of "natural causes", did it not mess up the order in any way? Maybe he was the starting point.
But I doubt mangaka would go that route.
My guess is the mangaka/the Student Council President is taking more of a "Final Destination" approach where "Death" decides someone is going to die and will not stop at making ways to kill those people, and in order if necessary (one of the films had a guy take a revolver from another character, point it to his own head and pull the trigger several times - every single round was a dud/light primer strike. "Death" actually prevented him from doing self-deletion until he was his time to die; it's a horror film but it actually makes "Death" itself out to be like the serial killer looking for a way to kill those that "Death" has to take).
So he's suggesting that because Satsuki is saving people (...that the President is trying to kill... so I don't think the mangaka thought that bit through that much) that "Death" will find a way to take make them die and will somehow be worse.
Now... If you look at the cover/page art from the early volumes,
the art seems to be implying this as well. You'll see earlier art of Satsuki covered in blood, a classroom totally in ruin and a bunch of corpses. Suggesting that eventually something drastic and mass casualty happens to take care of all the people she's saved.
...I personally don't think (and I hope) the manga doesn't go down that route, but... I would be surprised if the mangaka hasn't seen one of the "Final Destination" films and hasn't thought of this premise.