What kind of song do fish sing when they're having surgery?

What first appears the day after, takes over your muscles, and refuses to move out? Solve the riddle → Many avoid me, but most get me sooner or later. I am often small, but can cost you dearly. Solve the riddle → What silently reveals the passage of time in the mirror, unless constantly betrayed by the magic of the bottle? Solve the riddle → What is sharp, yet can never cut anything? Solve the riddle → What often disappears from its partner after spinning around in heat and suds? Solve the riddle →