Apologies. They are Alternian terms. [He struggled for a moment.] We are creatures with ties to insectoid life, I think is the term your species would use. So we are hatched from eggs and raised by a creature that is not our biological birth parent. That creature we call a lusus.

The slime is just what we sleep in at home, because it calms our nerves so we are not plagued by nightmares of blood and carnage until we are driven violently insane. Eating it rots one's thi.... brain. It made him incapable of handling his rage when he lost himself to it.