Someone who's victorian is particularly prudish or prissy. Your victorian math teacher might demand complete silence and expect to be addressed as "Sir."
When you describe someone as victorian, you mean that the person has an old fashioned, uptight idea of how others should speak and behave. You'll often see the adjective spelled with a capital V, since it comes from the other meaning of the word, "from the time period during the reign of Britain's Queen Victoria." Ever since the mid-1930's, people have described overly proper acquaintances as victorian, meaning that they seem like they're living in the nineteenth century.