What is he calls me boo?

"Boo" is a term of endearment that is often used between romantic partners or close friends. It is typically used to show affection and care for the other person. Some people believe that the term "boo" originated from the French word "beau," which means handsome. Others believe that it comes from the American slang term "boo-boo," which means an error or mistake. Regardless of its origins, "boo" is a common and popular term of endearment that is used by many people today.