Being used as a warning when someone speaks inappopriately and not family friendly to joke around usually with puns.
The origin is Beyaz Futbol, where four grown ups supposed to talk about football on TV but that is barely the reality. Rasim Özan Kütahyalı is famous by this inappopriate jokes in the show.
+I have a thirty centimeters definition of "ya rasim" between my legs.
-Ya Rasim! Children can read this.
+I will write a shorter one for them.
-YA RASİM!!