With TWGOK2 episode 8, it seems Manglobe finally learned how to do filler episodes with the manga material without stretching out the original chapter to fit into the timeslot. The two episodes that stand out in season 1 are episodes 4 and 12, “On A Crusade” and “More Than a God, Less Than a Human.” These correspond to chapters 17 and 6, respectively (yeah, they threw them into the anime in a different order, but I think the idea was to have the gag song end the season, which fit well with the contents of chapter 6). Funnily enough, the other “filler” episode done right was season 1, episode 8 as well, which corresponded with chapters 11 and 12. Why they were done “wrong” is just that the material for the manga chapter was somewhat filler, at least compared to the primary storyline. However, the anime episodes took these singleton chapters and stretched them out to take forever and a day, advancing nothing in the anime and ticking off people like me who read the manga :P
The episode that just came out corresponds to chapters 33 “Kami-Sama’s Dynamic Shopping,” and 27, “Tea for Three.” 33’s title was changed to “Her First Errand” for the anime. The first half of the episode deals with Elsie being taught how to buy video games for Keima so that he can extend his buying reach or something. The second half is the return of Haqua, where she consults with Keima and Elsie for a report on her soul capture. This episode is done “right” because it takes a couple light-hearted chapters and animates them, staying true to the original content. With as much material as is currently out in the manga, there’s no real need to make an entire filler episode out of a single gag chapter of manga (although TWGOK is still doing infinitely better than Beelzebub, whose anime is dead to me). Oddly enough, one of the main story points for “Tea for Three” was already brought up in a previous episode (I don’t remember which one), where Keima first learns of how many loose spirits there are (60k), and the other was skipped (how love is an uncommon capture method, and Keima learns that there are other methods to use). This has relevance for the Chihiro capture, which could be why “Tea for Three” ran before that arc; mainly, Keima realizes that he himself doesn’t need to fill the hole, as long as the hole is filled the spirit will be forced out.
From reading Rew Hawk’s message boards, it sounds like Wakaki originally did not have a ton of faith in this series as it was starting out, so he rushed through storylines rather than write them as his own longer pace. Hence, when the anime was announced, he was happy to be consulted on the story and able to provide more content for each heroine, which is why the Kanon and Shiori arcs were particularly long compared to their length in the manga. Personally, I found the pace of the manga quite good and felt I wouldn’t have been drawn in as well if more time was spent on each heroine arc. While I did complain about the gag chapters being stretched out in the first season, I thought they were done well, or like the content in the anime fit with how the chapter played out.
With the pacing for a 12-episode season, it seems like Jun’s arc will take up 3 episodes, then the season will end on another gag episode, plotting out the finale at the end of June. Let’s hope there’s another favorable announcement at the end!