The anime version consists of 51 episodes, and Episode 21 marks a critical turning point in the F4 dynamic. "Night of Betrayal".
In this version, Episode 21 is a heavy-hitter for the "soulmate" storylines and the lead-up to the finale. Hana Yori Dango Episode 21
If you mean the individual chapter, it features Tsukasa and Tsukushi getting stuck in an elevator, forcing them to spend uncomfortable alone time together. The anime version consists of 51 episodes, and
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