Takuma's younger brother as well as his twin. Oftentimes teary-eyed.

Mamizuka Umi (the P.E. teacher) is his mom and Mamizuka Kousuke (the actor) is his dad.

The manga centers on the brothers Ryuuichi and Kotarou Kashima. Ryuuichi is in high school and Kotarou is still a toddler. After their parents are killed in a plane crash, the two brothers find themselves living with the chairwoman of the Morinomiya Academy, who herself lost her son and daughter-in-law in the same accident. The chairwoman, however, has one stipulation for the brothers in order to live with her: Ryuuichi has to work at the academy's daycare center as a babysitter.
 
(Source: Anime News Network)

__Height:__ 157 cm

[Twitter](https://twitter.com/tanezakiatsumi) | [Actress Profile (Haikyo)](https://haikyo.co.jp/profile/profile.php?ActorID=12765)

Atsumi Tanezaki is a Japanese voice actress who is formerly affiliated with the Toritori Office, and is now represented by Haikyo.

In an interview with Repotama, Atsumi revealed that she became interested in doing voice acting after watching the anime series [Sailor Moon](https://anilist.co/anime/530/Bishoujo-Senshi-Sailor-Moon). She explained that her acting in the episode was so impactful that it encouraged her to pursue a career in voice acting. She began to study voice acting at a training school after graduating from high school in her home prefecture, Oita, using funds she had gathered from several part-time jobs. 

In the interview, she also states that her favorite voice actresses are [Miyuki Sawashiro](https://anilist.co/staff/95099/Miyuki-Sawashiro) and [Mayumi Tanaka](https://anilist.co/staff/95075/Mayumi-Tanaka), and as a child, she attended a [Junko Iwao](https://anilist.co/staff/95289/Junko-Iwao) concert, where she had the opportunity to talk to Iwao. Upon expressing her desire to become a voice actress at a fan event, Iwao responded stating that she looked forward to being able to work with her.

On October 2nd, 2023, she announced her marriage to fellow voice actor [Yuu Miyazaki](https://anilist.co/staff/127155).

**Non-anime roles:**
- Femirins - Houkai Gakuen (GGZ) (VG)
- Yoru Azuma - Hatsuyuki Sakura (VG)
- Hanako Tanaka - Tsujidou-san no Jun'ai Road (VG)
- Nagi Kodachi - Daitoshokan no Hitsujikai (VG)
- Masaki Gaillard - Amairo * Islenauts (VG)
- Anzu Takakura - Clover Day's (VG)
- Ichika Yuunagi - AstralAir no Shiroki Towa (VG)
- Sora Ousaka - Hoshi Ori Yume Mirai (VG)
- Nene Ayachi - Sanoba Witch (VG)
- Gretel - Kangokutou Mary Skelter (VG)
- Sora Niimi - 9-Nine (VG)
- Ayase Mitsukasa - RIDDLE JOKER (VG)
- Amleth - Memento Mori (VG)
- Sin - Goddess of Victory: Nikke (VG)
- Black Pearl Cookie - Cookie Run: Kingdom (VG)
- Vikala - Granblue Fantasy (VG)
- Seia Yurizono - Blue Archive (VG)
- Anby Demara - Zenless Zone Zero (VG)
- Riko Tanemura - Persona 5: The Phantom X (VG)

After their parents are killed in a plane crash, Ryuuichi and his younger brother Kotarou are taken in by the chairman, who they never met before, of an elite academy. Ryuuichi becomes the school daycare's new babysitter.


In the OVA's story from the manga's ninth compiled book volume, Ryuuichi takes a break from the babysitter club in order to study for tests. Imitating Ryuuichi as he studies, Kotarou and friends practice writing. Ryuuichi wants to thank Saikawa, who helped him out during testing, and he nonchalantly tries to figure out what Saikawa likes. Ryuuichi makes curry for the chairwoman and Saikawa. 

The OVA also includes a special "Snow White" segment based on a story from the manga's sixth volume. The chairwoman is the Queen, and Inomata is trapped in a castle doing nothing but studying as Snow White. Ryuuichi is the huntsman who takes her to the outside. The babies are the seven dwarfs, and they run into Usaida in the forest.
 
(Source: Anime News Network)

Kazuma Mamizuka