I cannot understand these sentences:" anything with an "o" in it" The text below is an extract from a film called The Vampire Diaries. Jeremy is a high school student who deals drugs. He's also in love with a girl called Vickie who is older than him. She works in a grill and uses drugs. She has been recently survived from a vampire's attack. She is compelled that she has been attacked by an animal not a vampire. In the extract below, she has left the hospital. Coming back to the grill, she meets Jeremy by accident. Jeremy: Vickie, what are you doing here? Vickie: Fighting with Robert about my schedule.You'd think getting ripped up by a rabid animal would merit an extra sick day. Jeremy: Are you feeling ok? Vickie: I hurt. Jeremy: Well, the doctor gave you something, right? Vickie: The kid stuff. Nothing with an "o" in it. I think they were onto me. [Jeremy gives Vickie some pills] Jeremy: Here. Knock yourself out, literally. Vickie: Thanks, Jer. Jeremy: So you gonna, uh, watch the comet later? Vickie: I hadn't really thought about it.But I could be talked into it. I'll meet you out there in a few. I cannot understand these sentences:" anything with an "o" in it"," I think they were onto me". and "Knock yourself out, literally". Why does Jeremy says "literally"?