A lighthearted Toy Story 5 anecdote went viral on Japanese social media this week after an X (formerly Twitter) user excitedly replied to a post about a fellow fan, only to discover the post was actually about her.
On July 4, 2026, X user @GOODBYE_KITTY3 posted that a follower had become obsessed with Smarty Pants, a new character in Toy Story 5, and was writing serialized self-insert fan fiction about them. The post joked that because Smarty Pants is designed as a potty-training toy, the fan fiction had taken the premise so seriously that toilet humor kept popping up as a recurring plot element.
The post caught the attention of another user, @roboinunununu, who replied asking who this fellow fan was, saying she desperately wanted to read the story. @GOODBYE_KITTY3 then broke the news: the fan fiction writer being described was her.
@roboinunununu responded with shock, before quickly turning her surprise into enthusiasm, thanking the original poster and promising to write more. She later admitted the revelation was honestly a bit of a shock once she saw how her own tweets had been characterized. @GOODBYE_KITTY3 clarified that the “fan fiction” label was something of an exaggeration, based on a handful of daydream-style tweets she had posted about the character.
The exchange spread widely overnight, and @roboinunununu said she was surprised to wake up and find her tweets circulating across Japan. She joked about eventually compiling her writing into a printed booklet, adding that she is studying graphic design partly for that purpose.
@GOODBYE_KITTY3 later used the post’s popularity to encourage fans to see Toy Story 5 in theaters and try writing fan fiction for any character they connect with, saying it could bring comfort to at least one person. Following the exchange, fan-created works featuring Smarty Pants reportedly increased noticeably on the illustration site Pixiv.
Who is Yuto Sano?
Yuto Sano (佐野勇斗) is a Japanese actor, singer, and member of the idol group M!LK. In the Japanese dub of Toy Story 5, he voices Smarty Pants, a new toy character designed for toilet training. His performance drew praise online, with some viewers saying they didn’t realize the character was voiced by an idol until they saw the credits.
Toy Story 5 is currently playing in Japanese theaters as of this report.
