RAW, the answer is clear: The ability doesn't specify an enemy, it specifies a creature. RAI, since it specifies a creature when specifying an enemy is possible and already done within the system (Bless only affects allies, Bane only affects enemies), it could easily be intended to be used on allies despite the name.  RAI doesn't nearly matter so much, however, since what's more important is how your group plays/what you want out of it.  If you are a group that encourages or at least allows optimization, I would allow the ability, since it's the sort of thing an optimizer would enjoy.  In the case of this Underpowered PC, I would recommend allowing it even if your game isn't terribly optimization heavy, just to bring the Oracle up to the party standard and allow him to participate.  I also recommend you be consistent about this, however, as it will be unfair if you allow one player to use an ability a certain way without allowing a different player to use it the same way.