module AboutAlma

sig Person {}

sig SoapOpera {
  cast : set Person,
  alma : cast,
  loves : cast -> cast
}

assert OfLovers {
  all S : SoapOpera |
    with S {
      all x, y : cast |
        alma in x.loves && x in y.loves => not alma in y.loves
    }
}
check OfLovers for 2 but 1 SoapOpera