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

Inline comments have to be preceded by at least this many spaces.
This is useful when style-conventions require a certain minimal offset.
Python's PEP8 for example recommends two spaces, so you could do:

(add-hook 'python-mode-hook
(lambda () (set (make-local-variable 'comment-inline-offset) 2)))

See `comment-padding' for whole-line comments.

You can customize this variable.

This variable was introduced, or its default value was changed, in version 24.3 of Emacs.