Tragedy is the opposite of Comedy. Comedy is related to Laugh. Laugh is related to Humor. Humor is related to Irony. 
Cream can be used for Soften. Cream can be used for Skin. Skin is related to Seal. Seal is a synonym of Block. 
Tragedy <--Antonym--> Comedy <--RelatedTo--> Laugh <--RelatedTo--> Humor <--RelatedTo--> Irony 
Soften <--UsedFor-- Cream --UsedFor--> Skin <--RelatedTo--> Seal <--Synonym--> Block 