comment-column is a variable defined in `newcomment.el'.
Its value is

  • Automatically becomes buffer-local when set.
  • This variable is safe as a file local variable if its value
    satisfies the predicate `integerp'.

Column to indent right-margin comments to.
Each mode may establish a different default value for this variable; you
can set the value for a particular mode using that mode's hook.
Comments might be indented to a different value in order not to go beyond
`comment-fill-column' or in order to align them with surrounding comments.

You can customize this variable.