Haraguro X

Haraguro X (ハラグロX) is a famous idol group that was first introduced in the Versus season of the Duel Masters Anime.

Details
They are an idol trio with a big fan base and sold multiple albums. Despite their appearances, they are strong duelists, evidenced when one of the members Erika obtained a total of 895 points in the Star Cup Preliminaries, a very high number at that time. They normally dressed as Nature Civilization creatures as their idol appearance, which might signify their main civilization.

Summer Concert
Erika accidentally bumped onto Bucyake on her way to work and helped him to pick up his cards. She then gives her phone number to him and invited him to be part of the concert. Katta Kirifuda, Lulu Takigawa and Hokaben were invited to watch the concert for free. They reveal that they are hosting an exhibition duel as part of their concert, with their new member Gomez as Bucyake's opponent. Despite Bucyake's loss, their concert was a success with the audience cheering for Bucyake for giving a good match. Bucyake then received the group's cards, Marignan, Dragon Edge, Erikatchu, Diva Style and Saepoyo, Charming Faerie as a gift for participation

Duel Masters National Tournament Finals Arc
The group was present watching the finals of the tournament by television in their dressing room.

Underground City Arc
Bucyake reveals that he have obtained more of the idol group's cards; X-girls, Snow Faerie and Torikera X, Revolution Rushkind as his trump cards.

Star Cup Preliminaries Arc
They host a duel concert in conjunction with the Star Cup event, with Erika revealing that she have obtained points during the preliminaries.