After Bon Kurei allied with the Straw Hat Pirates, they tried to escape Arabasta together, since the Navy was already after them. However, since Hina was using her well-known Blackcage formation, there was really no way to escape, especially since the Straw Hat Pirates was actually going to pick up another friend, Vivi.
However, Bon Kurei had a plan and wanted to sacrifice himself out of friendship with the Straw Hat Pirates so that they could pick up Vivi: He told his crew that he wanted to sacrifice himself out of friendship, and that anyone on his crew who would not do so was no longer his friend. Of course, everyone volunteered to sacrifice themselves out of friendship for Bon Kurei.
First the Straw Hats hid on their ship so that it would look as if they had abandoned it. Meanwhile, Bon Kurei had used his transgender fruit to transform himself and some members of his gang so that they had the faces of the Straw Hat gang. Now thinking that the Straw Hat Pirates was trying to escape on Bon Kurei’s ship, the Navy broke up the Blackcage formation and gave chase.
The climax is probably the fight between Bon Kurei and Hina, which unfortunately we can only guess at. Because exactly at the moment when Bon Kurei turns to Hina after he has finished off some marines, the picture switches back to the Straw Hat Pirates. However, it can be assumed that Bon Kurei has lost the fight, because we later learn that he and his gang have been arrested and imprisoned by Hina.Bon Kurei is later able to escape from prison.