For the muggles that don’t know, This is from Harry Potter and The Half Blood prince, the 6th book/movie, and is referring to Sectumsempra, which basically acts as a knife to sever you open. And after snape kills Dumbledore, harry tries to cast this on him
Dont be going all wE DidNT aSK yOu
I feel obligated to do this as a potterhead
Let me know if you know what any of that means or if it is just gibberish