on the line
When a bro only texts a girl when he's lonely or needs attention. Usually he's inconsistent and keeps her on a rotation with other girls. Basically leading a girl on through text. No commitment.
Example:
"yeah, i'm not really looking for a relationship right now so I'm just keeping this girl on the line."
"yeah, i'm not really looking for a relationship right now so I'm just keeping this girl on the line."