Mushikui is a bug-eating youkai that had been living in the Aoi's residence. Natsume first saw this youkai when he stayed there during his childhood.
Appearance[]
This youkai have no mouth but only two eyes.
History[]
When the younger Takashi Natsume stayed at the Miyoko Aoi's residence, this youkai had been harassing the young Natsume, telling him to draw a mouth for the youkai.
Plot[]
Back then, Natsume remembers that the youkai was much more smaller, thus he was able to resist the push.
However, later when Natsume visited the Aoi family, he noticed that the youkai getting much more bigger than he used to remember.
Nyanko-sensei informed that it was fine to leave the bug-eating youkai for at least 2-3 years, until it will consume the residence in house.
Knowing the fact, the terrified Natsume lured the youkai away from the house. Both he and Nyanko-sensei ran away from the chasing youkai. When they managed to escape and resting by the river, the youkai suddenly came and possessed Natsume.
The youkai feeds on Natsume's dark past, where he was always got bullied by the other kids, even his own cousin Miyoko hates him. The youkai asked Natsume to draw its mouth so that it could eat all the sadness that plagued Natsume.
Natsume managed to resist the temptation, which in turn banished the youkai from his body. Nyanko-sensei then eats the youkai into pieces of flying bugs.