It does not follow all of your rules, ahh well
Domain: Summoning (it fits, modify slightly so that all summons gain the [peep] descriptor and are extra tasty to anyone who tastes them)
Domain: The Peeps Below (modified version of the dragon below domain, all spell slots are summon peep X where X is the level of the domain slot of course, peeps summoned in this way have 5 Aberration hit dice per level used, have 16 in each statistic, all of their feats are toughness, and threaten their area but have no attacks or other special defenses; they start off size fine and gain one size category for each spell level increase; these spells have the [peep] descriptor)
Take a cleric who worships no particular diety in practice but believes he worships the Great Under Peep and all of his summons are from his realm. Unfortunately they are not very talkative or knowledgeable but with enough experience he can summon greater and greater avatars of that realm who will certainly know more....
Familiar? A giant pet peep. No, it has no statistics block, it is just an object. Probably. At least that is what you tell everyone. He is your special friend and will only talk with you anyway.