You're a couple votes from becoming a dictatorship in any democracy, by definition: 1) amend constitution or equivalent to allow the vote, 2) vote in the dictator, 3) there is no step 3.
In France, for exemple, you need first to have majority in both chambers (Senate and parliament) to validate the content of the modification. Then you need to have of 3/5 of parliament OR the majority in a referendum for apr roving the modification and putting it in the constitution.
And for almost every healthy constitutional democracy, it the same order of difficulty.