[Legacy of a Martyr #1] Masquerading the Key (A Key Keepers novel)

Alain Watanabe is a Key Keeper-a transient guardian with knowledge of other worlds. The time to act has finally come. The time to liberate his siblings is now. To do this, he needs to find seven keys to undo the spell that seals the palace of Engrada.
However, it won't be easy as mysterious individuals get in his way; ones who seek entrance into other worlds as well as other, more nefarious purposes.