Mr. Ayumu is violently pranked.
Here's a video from Panic Face King, a segment from a Japanese TV show. The guy in the white shirt and tie thinks he's at a business meeting. View the video first, then read below.
As far as I know, this clip is not staged or fake - this guy really had this prank pulled on him. But he wasn't some random guy pulled off the street - he was TV comedian Kato Ayumu, whose specialty is making funny faces. And many who've seen this say the show was not making fun of real sniper attacks or massacres - which are rare in Japan - but parodying the over-the-top violence you see on TV shows such as 24.
Here Mr. Ayuma is making another face. I don't know why.