The parasite house uses the former medieval city wall as a back wall. This forms one of the four house walls. Since one house wall was saved by leaning against the city wall, this is called a parasite house.
The 300-year-old half-timbered house is furnished with a shoemaker's workshop, furniture and household utensils from the period between 1860 and 1930. As a typical poor man's house, it tells of the hard life of a day laborer from Menden with his large family. Only a small detached piece of the medieval town wall in Menden has been preserved next to the Schmarotzerhaus.