It's an incredibly addictive and catchy number created by a Japanese caricature of a singer-songwriter called Piko-Taro, who has a YouTube channel dedicated to his work and musings.
If you haven't seen the original video, it features Piko-Taro singing and fusing an apple, a Pineapple and a pen, ultimately forming a Pen-Pineapple-Apple-Pen. It makes ** sense whatsoever, but that's why it is so utterly hilarious and magical. Read more...