With no explanation, label text_A→text_B with either "not_related" or "related".
text_A: Richard III of England died at the age of 64.
text_B: The pernicon is a type of fictional insectoid monster in the Dungeons & Dragons fantasy role-playing game .. Dungeons & Dragons. Dungeons & Dragons. fantasy. fantasy. role-playing game. role-playing game
not_related.