The cake, which already did not look delicious, reads "suck a nigga dick" at the bottom (possibly a reference to the Three Six Mafia track) and was not a cool gift from the sisters, brah. Even less cool was putting it on Instagram, but the fact that this person thought it was totally chill to publicly share a photo of a white chick smiling next to her "nigga" cake is kind of telling in itself. If you missed the slur in the photo, the poster also included the clever hashtag #suckaniggadick.
The sorority has already distanced itself from the situation, posting to Facebook:
We have become aware of an unacceptable Instagram post by a member of our chapter. The Fraternity volunteers and staff are working with our chapter at the University of Maryland at this time to hold this member accountable. Delta Gamma Fraternity is a dynamic organization committed to diversity and does not discriminate on the basis of race, religious affiliation, color, creed, national origin, sexual orientation, marital status or physical disability.
And before you get all nitpicky over how it's the lyrics to a song, which means it's not racist, just don't bother. No N-word in any way, shape or form for white people, ever, OK!? There is no wiggle room in that rule, no matter what milestone birthday you're celebrating.