I have been a little surprised in reading the replies to see there is no one magical regex.

tybalt89's single regex given here not sufficiently magical?!? You're a hard monk to please!

... passwords made by ... hitting immediately adjacent letters, e.g., "asdf." They must be next to each other: so "asdg" wouldn't match.

tybalt89's regex can easily be modified so that  'asd' 'wert' 'vbnm' etc. are rejected and  'asdx' 'xasd' 'xasdx' etc. accepted. This is left as a penitential exercise for a very demanding monk.