On gang signs...

Adam waves a car at the adjacent stop sign the go ahead after dark.
Jessie: You can flash your lights when it's dark.
Adam: Oh.
Jessie: Or gang signs.
Adam: Because I know a lot of gang signs.
Jessie: You could write "blood" with your hands.
Adam: I could write blood with their blood.
Jessie: That's only funny because it's coming from you.