PImage ikura, kome, maskImg;

void setup() {
  size(500,500);
  ikura = loadImage("ikura_s.png");
  kome = loadImage("kome.jpg");
  background(kome);
}
void draw() {
  if(sq(mouseX-235)+sq(mouseY-235) < sq(195)){
    noCursor();
    smooth();
    image(ikura,mouseX,mouseY,23,23);
  }
  else{
    cursor();
  }
}