Age old question, are the osa sentient pillows or normal yukkuri that grew bodies somehow?

Zekana said:

Age old question, are the osa sentient pillows or normal yukkuri that grew bodies somehow?

I've always thought of osa-yukkuris as an evolution of yukkuris, but maybe they're not because they don't have certain characteristics normal yukkuris have, so they're either another specie of yukkuri, or sentient pillows, but i think that they being living pillows is too weird