I love the concept of this game so much, very creative spin on a snake game! My only complaint is that the controls do not feel responsive. This is because the characters slide smoothly, but they can only turn and travel on a grid, causing the character to look like it's turns are delayed. If you ditched the smooth sliding of the sprite and instead just made them teleport to the next grid square every X interval, the controls would feel perfectly tight. Alternatively you could ditch the grid instead.
Either way, really clever and fun game mashup!