body, self
躬 centers on the physical self: one's own body or person. It refers to the self in a concrete, embodied sense.
躬 combines 身 (body) and 弓 (bow), likely suggesting a person bending the body, as when bowing. The exact historical development is uncertain.
The left side is 身 (body), and the right side is 弓 (bow). Picture a person bowing deeply, bending their body like a bow. This physical act represents the self or one's own body.
For キュウ, imagine a person bowing so deeply that their body makes a cute 'kyu' sound: kyu -> キュウ, and the bowing body represents the self.