Joining a sorority as a grad student

[amIblue?]

If you are speaking of NPC sororities, the answer to your question is that it can be both a hard and fast rule, depending on the sorority, and it can also vary based on chapter and campus culture. In other words, even if it is allowed by the GLO as a whole, the chapter does not have to take a grad student. For other GLOs, they mauls not be allowed to pledge a grad student, even if campus/chapter culture allowed for it.