Realm is related to Fantasy. Fantasy is a type of Imagination. Imagination is derived from Imagine. 
Organ is related to Skin. Skin is a type of Film. Fighter is a type of Film. 
Realm <--RelatedTo--> Fantasy --IsA--> Imagination --DerivedFrom--> Imagine 
Organ <--RelatedTo--> Skin --IsA--> Film <--IsA-- Fighter 