Roman is related to Mass. Mass is related to Gravity. Gravity is related to Law. Law is related to Deputy. 
Mushroom is related to Bell. Bell is related to Metal. 
Roman <--RelatedTo--> Mass <--RelatedTo--> Gravity <--RelatedTo--> Law <--RelatedTo--> Deputy 
Mushroom <--RelatedTo--> Bell <--RelatedTo--> Metal 