pulled in her chin

[suprunp]

Aomame pulled in her chin, kept her gaze fixed straight ahead, her back straight, and her pace steady.
(H. Murakami 1Q84)

Did she bend her head slightly forward so that her chin would almost touch her neck?

Thanks.

 

[SlickVic9000]

(Not a Teacher)

Exactly.
Doing this gives the appearance of intense concentration.