chumming the line
When a person sharts while wearing a thong or g-string.
"She thought she was going to fart, but ended up chumming the line in front of the whole pool party."
Chum Line
Being so friendly to someone you almost cross the line.
Jeff. I think I was so friendly to Bill last night that when he asked me to go into business with him I think I crossed the Chum Line.