I recently learned from my father-in-law that the reason they first met was because of their greek affiliations. (!!!)
FIL started out at CCNY taking evening classes while working during the day. He transferred and earned his bachelor's from NYU. Somewhere along the line, he joined APO. His chapter was all-male, and he nearly fell over when I told him that APO is now coed and one of my chapter sisters is a brother. (Shows how involved he became as an alum.

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MIL started out at NYU and transferred to CCNY. She pledged a service sorority, but AFAIK, was never initiated as her parents were dead set against any GLOs. (Funny how GLOs suddenly became ok when GMIL joined Kappa Delta Pi ... but I digress.) Neither he nor she can recall the letters. I suggested that it might be Omega Phi Alpha, but a little googling tells me OPA was founded after their college years and has not had a chapter at NYU or CCNY.
I am hoping someone can shed some light on this...?