Basically means to have a fuck buddy (usually for negative intentions)...
Person 1: I swear, I'll boof you if you don't tell me where my fruit loops are
Person 2: What the fuck is a boof?
Boof is a synonym for bitch, can be used in front of teachers or parents.
Brandon: You are so idiotic,
You: your such a boof.
Something you text your crush just to see what they will reply back.