Miura Hayasaka (Japanese: 早坂みうら Hayasaka Miura), is a close friend and classmate of Ena. She lives in a nearby high-rise condominium. She is boyish and brusque, in both her appearance and speech (this is very noticeable in the Japanese version; see gender differences in spoken Japanese). Sometimes, she can be too straightforward and insensitive, and she counters aggressively in a tsukkomi-like manner if she feels mistaken or made fun of. Because of this, Miura appears less kind and thoughtful than Ena, but she is aware of others' feelings. For example, she immediately notices Jumbo's infatuation with Asagi and uses it to her advantage. She is also extremely squeamish: when Jumbo takes the younger children fishing, Miura refuses to handle live bait, using salmon roe instead, and hides while Jumbo and Ena clean their catches; she is also terrified by a large frog Yotsuba catches. Miura often wears sports-related clothing (such as jerseys of the Los Angeles Lakers and Los Angeles Dodgers) and rides a unicycle. She is sometimes called Lamborghini Miura by Jumbo.
Miura is 121 cm tall (4'0'').