As the fans eagerly await to enter the toilet cubicle with Diamond Vacuum, Otae and Sacchan compete with each other to see who could attract more fans. Turned off by their boorish behaviour, they turn to the quiet Kyuubei. However, she was unable to get used to a man's touch and started throwing the fans who tried to shake her hand. Tsukuyo appears to help her, drawing both the affection of Kyuubei and the fans. Annoyed at her laidback attitude and still bitter over the events of the Character Poll Arc, they stir up a scandal about Tsukuyo. The two women start a physical argument, and the remaining fans leave.
Meanwhile, GKB48 has managed to captivate many fans, and Bichie tells Booger Diamond 48 that the battle is over. Shinpachi rebuts this and tells Otsu, who was watching the battle on television in her room, that she would always have a fan in him. Shinpachi enters the tent and falls out a few seconds later, seemingly bewitched and defeated by Bichie. However, he reveals that he actually pulled out one of her antenna, causing her to transform into an ugly Amanto. Takachin and the other members of the Otsu fanclub also reveal that they have done the same to the other 47 girls, who were all ugly aliens disguised as cute idols. GKB48's brainwashing did not have any effect on Otsu's loyal fans.
Drawn by the passion of Otsu's fans, the rest of the fans run towards Booger Diamond 48's side. Unwilling to be defeated, GKB48 emit sound waves to brainwash the fans. Kagura attacks Bichie, while the Diamond Vacuum backing band play awful-sounding music to cancel out the brainwashing sound waves.
Bichie said that an idol's dream is nothing but lies and illusions. Gintoki tells her that like samurai, idols strive to improve themselves and chase after their ideals. Bichie realises that the entire battle acted like a massive booger, to make a diamond like Otsu shine brighter. Kagura tells Otsu, who has arrived to the stadium, to perform Booger Diamond 48's latest song, as she punches Bichie out of the stadium.
Later, a defeated Bichie tells Otsu's mother that Otsu was able to shine brightly by walking over the dreams of her friends. As she watches Kagura leave the stadium, she tells Otsu's mother that she had let go of a talent that could surpass Otsu - a girl who had the ruthlessness to take down her enemies and the selflessness to cast her own dreams aside to help her friends, a diamond covered with booger. Otsu's mother reveals that she had asked Kagura if she wanted to continue going down the path of an idol, but she declined as she was already part of her own idol group...the Yoruzuya.
In a post-credits scene, Kagura overhears a young girl talk about Kagura while watching Otsu's performance on a television in a store front. The girl said that something was off about Otsu lately and that she must have been influenced by an idol group she loved - Booger Diamond 48. Kagura tells the girl that the group would always remain in her heart as the idol group of dreams. The scene pans out to show both Kagura and Otsu digging their nose.
- Sakata Gintoki
- Shimura Shinpachi
- Shimura Tae
- Yagyuu Kyuubei
- Sarutobi Ayame
- Terakado Tsuu
- Terakado Ichi
- Hachibei Takaya
- The episode makes references to Clift, Burai and Alena from Dragon Quest IV.