Add interaction with Benign Souls: http://www.minecraftforum.net/forums/mapping-and-modding/minecraft-mods/wip-mods/1445975-evilcraft-open-source-v0-9-3?comment=516
Further suggestions: http://www.minecraftforum.net/forums/mapping-and-modding/minecraft-mods/wip-mods/1445975-evilcraft-open-source-v0-9-6?comment=568

Have a look at SoulRegistry#isSoulPresent, and the API once it's released.

Intangible is not being maintained anymore.