Walking Heart takes on a feminine humanoid-appearance almost entirely comprised of long, thin, rigid strands. It lacks a nose and a mouth, having only emotionless lens-like eyes and long, rigid hair. On its chest is a large heart, surrounded by a smaller heart on each side and a heart-shaped collar around its neck. Around its waist is a belt with several ridges and another heart in the middle.
In the colored manga, Walking Heart is depicted as primarily red with yellow eyes.
Not much is shown of Walking Heart. Although it possesses a form, its power has so far only manifested as an ability that Hato uses for direct combat.
Although straightforward, Walking Heart's speed and power makes Hato a surprisingly deadly fighter.
Walking Heart allows Hato to turn the heels of her shoes into hardened spikes, making them extend to as much as 4 meters.
The transformation and subsequent reversal are fast enough to outspeed human reaction time. These spikes can penetrate any surface, including glass and stone as well as other human's (or Rock Humans') bodies.This allows Hato to walk up walls with her heels digging directly into the brick or other materials, as well as attack with her extended high heels with kicking motions.
It is unknown if Walking Heart can extend other objects in this fashion.
- In keeping with the Higashikata Family naming trend of their Stands, Hato's Stand also has "king" within the name (Walking Heart).