So I was browsing and lurking and shaking every possible description of this gif at google but so far i got nothing. It is of a dark skinned girl, walking through a door with a smile on her face.

Like, she surprised her principal having done the nasty with her hated stepfather and is on the way to let her best friends know. She also carries a tote. Possibly filled with proof. But that's just speculation and makes for a better image representation.

Can you fellow ATRLers help an old fossil like me? Thank you very much <3

This?

YES! Thank you. Case closed.

There's a thread called "Where is that gif" and the gif you were looking for is literally in one of the 3 last pages.