Well, i like the idea that Ceodore posted. But, i don’t really see how a pet class would work for a tank. From what i’ve read in the OP, the pets are mainly meant as a buff, rather than an actual pet like the Egi’s.

We can’t really have a Pet be a tank, unless we have full control over the actions the pets had, especially for keeping hate and popping the proper buff for each situation. Because of that, it’s better that the character him/herself would tank the target, while the pet is on the sidelines for support.

When you look at it like that, i would rather see something like what Iagainsti said earlier, a skill or stance that would give the caster or it’s party members a buff. Or maybe a combination of both, like skills that could only be used when you are in a certain “Spirit Animal” stance.