very good game. i like the concept ideas, and the story behind it. the last level i found quite cool, at least the way i solved it; jumping repeatedly off a cliff until luck lands you on one of the "clones" then jump again.
i understand this as a short game...
but perhaps you can have it where you have to burn multiple ropes, or even better perhaps, multiple levels if your are creating another version (doubtful. would be cool though)
Kuro, you need to add boundaries...
if(this.y>TopY){
this.y=+speed;
}
if (this.y<BottomY){
this.y=+speed;
}
repeat for x. its something like that. also,( i guess you are using movieclips on this?) you could improve the graphics.
 "You are a...")
 "The Company of Myself")
 "Toss the Turtle")
 "You Have To Burn The Rope")
 "Run")
 "Elements")
 "Penguin Shooting Game of Terrible Art")
 "Vindex Gladiator")