Tarai mawa shi-hen (盥回し編, Rota tion Chapter) is an arc found in Higurashi no Naku Koro ni Matsuri and most subsequent console ports.

At first glance, this arc appears to be a re-telling of Onikakushi-hen. However, this chapter also contains elements from Watanagashi-hen and Tatarigoroshi-hen. After learning the secrets of Hinamizawa, Maebara Keiichi, instead of going crazy, decides to ignore everything and enjoy his peaceful school life. Unfortunately, this does not prevent tragedy from striking. Sonozaki Shion is the villain of this chapter, while Sonozaki Mion, like in Watanagashi-hen and Meakashi-hen, becomes the victim.

Tarai mawashi, literally "pass the basin around," is a Japanese idiom referring to someone avoiding a necessary but unpleasant task by passing the responsibility on to another, similar to the American English phrase "passing the buck."

The ending of the anime arc Yakusamashi-hen contains very similar events, and it is likely the scene was adapted from Tarai mawa shi-hen.

Endings

As part of Matsuri 's non-linear storyline, Tarai mawa shi-hen arguably has two endings despite the arc itself being linear. Playing through Tarai mawa shi-hen leads to the first ending, but completing Tsukiotoshi-hen unlocks a TIP that contains the second ending which follows on directly from the first. This structure is somewhat similar to Tsumihoroboshi-hen and its epilogue TIP "The Devil's Script".

Ending 1

Mion survives the Great Hinamizawa Disaster and ends up in a hospital in a state of mental shock she got from all the horrible things happened to her. Akasaka and Ōishi visit her in 1993, 10 years after the events in Hinamizawa and Ōishi talks to her about the disaster, but Mion doesn't respond and starts to shuffle cards for the long dead Club members. Ōishi explains to Akasaka that Mion has been stuck in the past for 10 years and she still acts like her friends are still around. The detective then angrily asks Mion to tell him what she saw on the day of the gas disaster. The arc ends with Mion saying "...What should this game's punishment be...? Please tell me... okay, Kei-chan...?".

Ending 2

After their questioning in Ending 1 proves futile, Ōishi and Akasaka decide to show Ryūgū Rena's blood-stained hat to Mion, but still get no response from her. After they leave, Mion realises the meaning behind the hat and recovers from her shock. She asks her nurse to call Ōishi back, but is found dead the next morning, leaving it unclear whether she got the chance to talk to him about the disaster.

Disappearances and Deaths

All deaths and disappearances are listed only as they are told in Tarai mawa shi-hen. Spoilers are only for the individual arc, not the overall series.

Disappearances

Hōjō Satoshi, went missing a few days after the 1982 Watanagashi Festival.
Sonozaki Shion, went missing on June 20, 1983.
Ryūgū Rena, went missing in the GHD, only her blood stained hat was found in the river flowing through Hinamizawa.
Over 20 residents of Hinamizawa, went missing in the Great Hinamizawa Disaster.

Deaths

Tomitake Jirō, scratched out his own throat after the night of the Watanagashi Festival.
More than 1200 people, died from volcanic gas poisoning on June 22, 1983 in the Great Hinamizawa Disaster.
Sonozaki Mion, died from acute heart failure in the hospital where she was treated in 1993, 10 years after the Great Hinamizawa Disaster.

Trivia

What is it that you want to see? I shall show it to you.	What is it that you want to hear? I shall tell you about it.	But, please don't expect anything. For you who close your eyes and ears, surely, it is meaningless. Frederica Bernkastel

This scenario functions as a "punishment" for when the player fails to get into any of the other arcs, and makes it clear to the player that they cannot simply avoid the tragedies around them and expect a happy ending.
On the first playthrough of Higurashi no Na ku Koro ni Matsuri, the only available arcs are Tarai mawa shi-hen and Oni kaku shi-hen (though Wata naga shi-hen can also be accessed by saving and reloading). If the player makes certain choices during the common route and then chooses to talk with Tomitake and Takano after the Watanagashi Festival, the events of Oni kaku shi-hen will start. Choosing to talk to Shion after the festival or failing to make all the right choices earlier will send the player into Tarai mawa shi-hen instead. However, despite Tarai mawa shi-hen being the easiest arc to unlock, completing it is not required to reach the ending of Matsuri.
Tarai mawa shi-hen is almost unique among Higurashi arcs in requiring its "true ending" to be accessed via a different arc. The only other case of this is in Matsuri, where completing Tsuki oto shi-hen also unlocks the Tsumi horobo shi-hen epilogue "The Devil's Script". (In all subsequent console ports, "The Devil's Script" was unlocked via Tsumi horobo shi-hen as normal.)
Chronologically, Tarai mawa shi-hen takes place before Oni kaku shi-hen.
Tarai mawa shi-hen is the shortest "main" visual novel arc in the Higurashi no Na ku Koro ni series, though most of the arcs from Rei and Hou are even shorter.
A fan translation of Tarai mawa shi-hen can be found here.

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