Those things that devour from the inside.

Just finished a small drawing of an imaginary parasitic wasp, based on various insects but mainly on Chalcid wasps, which use other insects as hosts, often laying eggs inside defenceless caterpillars, some waiting around for the caterpillar to pupate, then laying eggs inside the cocoon, where the chalcid larvae feed on the internal organs. Others are parasites of different wasp species.

0.05 point pen on white card. Most Chalcid wasps are tiny, the largest being around 3 - 6mm long, so I guess this one is around 45X lifesize.