Here a quote:
Somali and Boni nomads make use of two types of headrests; one with a single cylindrical supporting column and one with a double column. It appears that the different styles are for men of different status, with the single-columned variety for young men and the double-columned variety reserved for elders. The more elaborate the headrest is, the higher the status is of its owner.
My first print was with too wet TPU, so that's why the model looks hairy. Turns out that the head rest is actually pretty comfortable, although the two arms are too soft (with TPU).
References
The author marked this model as their own original creation.