'My Wife Will Become an Elementary School Student') is a Japanese manga series written and illustrated by Yayū Murata.

One night, while having store-bought dinners, they answer the door to an elementary school student named Marika Shiraishi, who claims to be a reincarnation of Takae.

Takae immediately scolds both of them for living such unfulfilling, sad lives and helps them get back on track by helping Mai get more confident and pursue a more social job, through which Mai meets a seemingly rude and blunt, but actually kind man named Renji Aikawa, whom she ultimately gets close with and decides to marry.

Takae, through Marika, also helps Keisuke regain his old cheery but rash self by meeting with him often to give him handmade bentos.

Although happy that Marika is occupied when she is busy, it is revealed that she has developed an irritable personality after having her ex-husband leave her due to a gambling addiction and not having caring parents herself.

She does regret her past actions and is shown to truly care for her daughter as Marika discovers a photo from long back, consisting of her and Chika smiling at an amusement park inside a box named "Treasure".

Slowly but surely, with the help of his colleague, Konomi Moriya, he begins to have a more positive outlook on life and starts to become more self-dependent by making his own bentos, learning to live without meeting Takae/Marika often and not being as rash as before.

They finally decide to stage a fake proposal between Keisuke and Konomi to convince Takae that they have moved on from her demise, which leads to Takae's soul finally having no regrets and for her to leave Marika's body, leaving for her heavenly abode to rest in peace, urging her daughter to "be strong and live a good life".

Finally, the story ends with everyone having changed as people from this entire experience, with Izumo's other soul moving on as well after confessing to the partner he wasn't able to in the past, with Marika's and Chika's relationship improving, and with the Niijimas finally having learned to live their life with no regrets, Mai having a daughter with Renji and Keisuke shown to be living with happiness with his own now happy family.

[30] It was directed by Toshio Tsuboi, Takeyoshi Yamamoto, Maiko Ōuchi, and Naoki Katō, based on a screenplay by Satomi Ōshima [ja], and the music was composed by the instrumental band Pascals.

[35] Yako, Shōgakusei ni Naru, a spin-off series featuring an original story, was released on the Japanese streaming service Paravi from February 11 to March 25, 2022.

Hidetaka Sakamoto, Hiroyuki Tamekawa, and Saya Hirosawa directed the series from a screenplay by Masashi Suwa.