I've been thinking about this concept for a while as a concept project: re-frame the 77 demons of the Lesser Key of Solomon (Lemegeton Clavicula Salomonis), a weird dark magic/demonic text written in the 1500s or so, as a guide to Daemon Princes in warhammer/warhammer 40k.
First of the 77 daemons is Bael, shown as a man/cat/toad with control over 66 legions of demons and the power of invisibility.
using this description and his runic symbol, I came up with the above, a daemon prince of the pantheon that is aspected to darkness and invisibility, a great toad-like creature with hints of the cheshire cat. Hope you like!