These 3 are practicing some special musical instrument made out of small sand bags so when you shake them and collide them they produce a distinct beat.
And a young girl hiring a photographer to preserve her precious memories.
When I exited the park on my way to the subway station, I noticed a huge crowd across the park at the Yoyogi National Stadium.
Oh! It's the Ayumi Hamasaki (浜崎あゆみ) concert!!! The items you saw are souvenirs and they're selling like crazy. The concert will take place tonight, tomorrow and Dec 31, with the last one having a count down to the New Year with her fans. I haven't listened to her songs, but she's supposed to be the most successful J-pop singer since the beginning of J-pop! I also heard that she wrote all the songs' lyrics herself.
Lastly, a group of fans posing before entering the concert venue.