She remembered watching an episode on 'Animal Gangsters.'
Where it mentioned that there were certain types of caterpillars that were able to fool other insects into rearing it as their own larvae.
Eureka!
This is what the demon caterpillar had done to the demon locusts.
Hitching a ride on the demon locusts back it secured food for itself by hiding wherever the demon locusts hid their larvae.
The demon caterpillar let out that sweet smell as an overcoat.
This overcoat was composed of a similar smell to larvae of the locust.
So it was able to grow with them by feeding on its host.
This particular demon caterpillar makes a waxy overcoat when it feels threatened.
Quickly wrapped its enemy up in a gelatinous cocoon to feed on for future meals.
Judging by its size this one was a glutton and had been feeding on its hosts for several days.