In the picture, which can be seen above, Bieber is wearing a Japanese school uniform type outfit and touching Pikotaro's chin.
It was a September tweet that Bieber sent out to his 88 million followers, calling PPAP his "favorite video on the internet," that helped make the wacky little song about a pen and a pineapple the viral hit that it eventually became.
No specific information was given about where or why the two met. However, it seems like this may be related to the the Softbank ad campaign that Bieber is currently appearing in. If that does turn out to be the case, then we may be getting a commercial starring both Bieber and Pikotaro in the very near future.
If you'd like to read more about this new ad campaign and see a Softbank commercial featuring Justin Bieber then click here.