Bits and pieces that Hashimoto Takashi uploaded on his Twitter account while he was still active.

Rough drafts for Irabu [archive]

Genga [archive]

'A signed piece for a certain person' [archive]

Fun fact: the real-life face of the kid shown in episode 11 is Hashimoto's son. You'll have to take my word on this as I didn't think to archive the tweet I saw from him at the time. But I think it's a neat little piece of trivia.