I think Shiba's sorcery cannot actually do X
EDIT: Apparently I'm already wrong, ha! Accordingly to those that know japanese, the way it's written in Japanese is "physical body height" as in size. So what I was interpreting is invalid. Oh well, I take the L
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> ... freely maniplating their (positional information and physical properties), such as height, weight, and so on.
The text is actually listing examples for his ability as a whole. So "height" is an example for "positional information" manipulation, and not for physical property manipulation.
The "height" in its description is probably the height of the object position, so its Y coordinate if we go with the X/Y/Z spacial coordinate system. So changing an object's height means teleporting it up or down.
From what I recall, no where in the whole manga Shiba has manipulated an object size. He probably can't make an object "bigger" as in "higher".
Shiba's ability as shown on-screen seems to be:
- teleporting (manipulating x,y,z coordinates, with "y" being "height")
- increasing/decreasing weight
- manipulating speed (many times Shiba seems to teleport from a "resting" position to another place already while already in movement)