By reading this blog, I'm guessing the Pirate's Bless is like BoF or something like that.

http://orangemushroom.wordpress.com/...summer-update/

Raising a Cannon Shooter will give all your other characters ‘Pirate Bless’, raising Mercedes will give you ‘Elf’s Blessing’, and raising a Demon Slayer will give you ‘Demon’s Fury’.