Pappu has become a label stuck on the identity of Congress president Rahul Gandhi and by the same token Feku has come to be associated with Prime Minister Narendra Modi. Have you ever wondered as to who coined these expressions? Incidentally both are attributed to former actor-turned-politician who crossed over from the BJP to the Congress recently, Shatrughan Sinha.
However, Pappu was popularised by BJP president Amit Shah in the 2014 election campaign when he is reported to have said at a rally, that some people think Primeministership is a pappu's birthright. The label stuck and thanks to Google and its instant search results, Rahul Gandhi could never quite shake it off.
As for Feku, it seems to have been coined more as a response to the already popular pappu, but it took very little time for it to gain currency on social media. In a television show, Shatrughan Sinha Sinha reportedly also took credit for coining the name NaMo for Narendra Modi apart from Pappu for Rahul Gandhi and Feku for PM Modi.
Regardless of the veracity of Sinha's claim, all three tags have become extremely popular in social media also in popular imagination. They are widely used in sarcastic jibes and to take pot shots at one another.