Mina has long brown hair, which she usually keeps tied back into a ponytail, and very short bangs. Most notably, she has thick eyebrows and large brown eyes. She is noticeably shorter than most of her classmates, making her appear much younger than she actually is.
Mina is an energetic, bubbly girl and is usually cheerful and optimistic around others. She is especially playful and noisy around her two closest friends, Sanae and Yukari. While she can often be hard on herself sometimes, she usually snaps out of it, as she hates being in a somber mood.
- She tries to drink coffee to seem more like an adult, but ultimately fails and had to trade drinks with Sanae instead.
- She enjoys orange soda as a beverage.
- In the manga, Karakai Jōzu no (Moto) Takagi-san Chapter 72, it is revealed that she is the teacher for Chi (Takagi and Nishikata's daughter) in kindergarten. The chapter also reveals that she already has three children, while the identity of her husband is still unknown.
- Mina's age in the spin-off is never revealed, but estimated to be around 26 - 27 year old.
- Her age being around 26 - 27 year old is due to the fact that she went to the same school and class with Takagi/Nishikata. In Chapter 31, Takagi mentioned "it has been over 10 years since those days in middle school" while reading through her middle school graduation album. Since the age students graduate from middle school in Japan is 14 - 15 year old, then add over 10 years to it. 14 to 15 plus more than 10 is around 26, at the least.
- She has a very sensitive tongue and can't handle the taste of carbonated drinks, even into her adulthood.
- She is the cousin of Hibino (who was never given a first name) from Fudatsuki no Kyoko-chan, another one of Sōichirō Yamamoto's works.
- This was seen in Episode 11/Season 2 of the anime and Ashita wa Doyōbi 21 when Mina sent photos of her with her cousins to Yukari and Sanae.
- Creator Sōichirō Yamamoto confirms this in his Tweet with a picture of the two cousins and the text "いとこの日々野さん２人," which roughly translates to "two Hibino-san cousins."
|Main||Takagi • Nishikata|
|Supporting||Mano • Nakai • Sanae • Yukari • Mina • Takao • Kimura • Hamaguchi • Houjou • Tanabe-sensei|
|Minor||Sumire Takagawa • Tunnel Fisherman • Tunnel Fishergirl • Tunnel Misc • Principal • Mano's Friend • Class 4-2 Unnamed Girl|