Organizations after undergrad that are like fraternities in terms of brotherhood?

[naraht]

I know at least one of the service greeks gives chapters the option to have grad students join, but he did say "a group of guys".

Are there any social fraternities/sororities (defined as exempt from Title IX and thus single gender) that allow their chapters to have students going for a masters/doctorate to join?

For example, would a grad student at Howard University be able to go on line with the undergrads for Kappa Alpha Psi (or any NPHC) or should they go Grad Chapter?

For NPC sororities that allow AI, would a grad student be able to go AI? (Yes, I know the original poster is a guy)