sista lorten stänger porten

Swedish

sista (“the last”) +‎ lorten (“dirt, filth”) +‎ stänger (“closes”) +‎ porten (“the door”)

the last person to enter (a house or the like) should close the door
Glöm inte att sista lorten stänger porten när ni lekt färdigt
Don't forget to close the door when you come in after you're done playing