Big Bang frontman G-Dragon was one of the special guests at Psy's Happening concert in Seoul on Saturday.

The young, prolific performer took to the stage with his single "One of a Kind" and the crowd in the Seoul World Cup Stadium went nuts.  The 50,000 fans went instantly crazy.  

After the song, GD talked to the audience.  He had many words of praise for his "older brother" Psy.  The singer-rapper told everyone that he had begged Psy to let him appear at the concert becasue the shows are famous for their incredible energy and high excitement level.

Psy had mentioned that in the past, his concerts usually catered to an older crowd.  GD addressed the audience on this matter saying, "I like the older crowd too. I am 26 now, afterall. Can I pretend that this is my concert for a moment?" to which the fans response was clear, absolutely he could.

G-Dragon then gave a performance of his hit song "Crayon" followed by BigBang's successful single "Fantastic Baby" and finished off with another verse of "Crayon."

It was an exciting break from Psy for a moment at the Happening concert, and G-Dragon was very grateful to all the attendees for their energy and dancing.