[quote="Kallo"]I'm also having this weird fear where I really hope Jasiri wasn't just a one-time character they plan to never have back in the series. I really liked her and I hope they aren't silly enough to just forget about her. Despite her huge popularity, so far Disney really hasn't marketed her at all in any form or fashion, which makes me kinda worried about the character's future in the show.

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It could also be that Disney underestimated how popular Jasiri would be and didn't make any plans to capitalize on her popularity.
As for Bunga being the one to misunderstand what Raifiki's painting can do. It is because he is the character most likely to get something wrong. Yes Bunga has made mistakes before, but as he is the character most prone to overlook details. He is also most likely to make a mistake again.
Also Kion made the mistake of thinking that Fuli should never be left alone in Fuli's New Family. he was also the one that let Dogo into The Pride Lands. So he has made some mistakes.
The Mbali Fields Migration is set in The Outlands. Perhaps The Lion Guard will need Jasiri's help to get the herd safely through?
With Bunga and The King I will be shocked if Simba doesn't already know Bunga's back story. I'm sure Simba would be well aware of Timon and Pumbaa taking in another animal. Especially his son's best friend.