There are endless reasons to celebrate anime, but the beloved characters who star in series are an indispensable part of the process. Impressive visuals and a surprising story can only go so far without compelling characters that tie everything together and bring individual emotion to these universal events. Many anime begin fully-formed, or they're able to assemble their core cast after only a handful of episodes, like Yu Yu Hakusho or Fruits Basket.
Source：https://www.cbr.com/best-anime-characters-only-appear-after-first-season/
