Officer candidate school questions?

I know two people that say that they can graduate from college and go straight to officer candidate school. They don't know each other. Neither are in ROTC or anything like that, and neither have talked to a recruiter yet. One of them is on his 7th year undergrad for a business degree (and he's never changed his major), and has a really bad GPA (like always on the brink of being kicked out). Can you graduate with any degree, go right to officer candidate school, then go right in as an officer? This doesn't seem right to me. Can someone tell me how it works?