"Recollection Of A Most Sincere Apprentice" (一番弟子の回想, Ichibandeshi no Kaisou) is an extra chapter included with Volume 7.
This chapter follows Charanko, as he is about to leave Bang's dojo. Charanko joined one year prior, in order to become popular with girls. Because Charanko is not a very good martial artist, he has always done all the chores in the dojo, and was frightened of his Senior, he also has not become any stronger or popular, so he decided to quit. When Charanko arrived at the door, he was surprised to find his master cleaning the floors, when he asked him why, he was told the others have all quit. Learning he was the only disciple left, he came to a realization that he is now the number one disciple, and so he decided to stay and work even harder.