A "quopic" is: combining two words into one and used as short-hand. The two words are "quote" and "picture". For those too lazy to write each word separately.
French expression used to prank someone who has just said "quoi" ("what" in french).
It finds it's meaning from the fact that "quoi" is pronounced cou-a, so saying quoicoubeh is essentially saying "cou-a, cou-b", kinda like another popular french joke that occurs when people say "ah" because they are surprised, and you answer "b" because you're extremely unfunny.