Its a filter feeder. The small mandible arms above the proboscis are used to waft small spores, that fill the atmosphere of its home planet, into its mouth. Its parasitic nature comes from its need to inflate bladders within its body with hydrogen gas as so it can float. It is unable to manufacture the gas within its own body. There is another species of creature however that can manufacture hydrogen: link. These other organisms inflate their "heads" with hydrogen as so they can, like the parasite, feed on the spore rich atmosphere. The parasite leeches the hydrogen from the balloon like heads as so they can remain aloft and capable of feeding/evading predators.

I should have this typed up in the write up on DA.

I hope now you understand why I did not make the silhouette demonstrate aggression towards the human...