All the red slowly drains away, but that's what I want.

 The red drips away, but that's what I want it to do.

 The red is where I want it, out and gone. 

The red will leave, then I'll have nothing left. 

The red is calming as it drips down. 

The red is what I want, I want to be gone. 

The red slowly drains and drips away.

 The red is all gone, so goodbye.