The youngest of the three sisters, Hina Takanashi is 3 years old and attends kindergarten. She is the biological daughter of Yuri and thus the only one of the three girls who is directly related by blood to Yūta. She is very friendly and unafraid of strangers. She sometimes mispronounces words, often leaving out certain consonants. She normally addresses Yūta as "uncle (Oji-san)", but has trouble with the "j" and "s" sound so it comes out as "Oi-tan". She is a fan of the heroine anime, Luna Luna Seven.
As of the 2nd OVA Hina's speech clears p and she can speak properly without any problems with the "j" and "s". She also starts to look act and a little more mature than when she was three.