During last night's Kanjani8 concert at the Tokyo Dome, Yokoyama surprised everyone by inviting out a special guest: Sakurai Sho!
During the MC, Yokoyama talked about The Quiz Show (as he did the previous night). Sakurai Sho was also mentioned at this point. Towards the end of the MC, Murakami announced, "There's a surprise guest here tonight. Yokocho, why don't you introduce him?"
At this point, the audience started getting really excited, and Yoko made his naughty little boy face and shouted, "It's Sakurai Sho!" The doors to the dugout opened and the spotlight moved over to where Sho was standing. He was wearing a Kanjani8 t-shirt and waving a Yokoyama uchiwa.
Sho climbed the stairs and hurried to the main stage, waving his uchiwa the whole time. He stood by Yoko the whole time and seemed very nervous. My Japanese isn't the greatest, so I couldn't understand exactly what was going on.
The other Kanjani 8 members asked him something about Yokoyama's character on The Quiz Sho, Honma. Then they asked him to act like Kamiyama and Sho gripped his head and shouted in pain Kamiyama style.
As the MC was winding down, Sho put his Yoko uchiwa in his back pocket and started running off the stage. The uchiwa fell out of his pocket and the other members kept shouting for him to come back and pick it up. He came back and embarrassingly picked them up. Then he stood at the bottom of the stage and waved to the audience for a minute or so.
Sorry that I can't give a word for word translation of what happened. I'll check some Japanese fanreports and try to give a better report at a later date.