The Golden Fish can be used to turn normal cats into Queen Cats, heal them, and also craft the Kemomimi Potion, you can eat it too and it will work like a Golden Apple (may be disabled on later versions).

The Golden Bone can be used to turn tamed Wolves into Queen Dogs.

The Golden Wheat can be used to turn Rabbits into Queen Bunnies.

The Kemomimi Potion it's crafted from Golden Fish, Golden Bone or Golden Wheat, it can be used to turn Cats, Wolves, and Rabbits into their Queen Variant, also can be used to breed Queen Cats, Queen Dogs and Bunnies, and make Princess Cats, Princess Dogs and Princess Bunnies grow faster.

The Queen Cat can be obtained by using a Kemomimi Potion on a Tamed Cat, if spawned using Spawn Eggs, you can tame it with Golden Fish, they can be healed with any kind of raw fish (except pufferfish), you can also give them a Vanilla Chestplate for them to wear with Shift + Right Click, that also opens up their inventory.

Dyes (Black, White, Orange and Gray) can be used to change their colors.

The Queen Dog can be obtained by using a Kemomimi Potion in a Tamed Wolf (which you own), if spawned using the Spawn Eggs, it can be tamed with Golden Bones, you can heal them with any kind of meat a normal wolf would eat, you can also give them a Vanilla Chestplate for them to wear with Shift + Right Click, that also opens up their inventory.

Dyes (Black, White, Gray and Pink) can be used to change their colors.

The Queen Bunny can be obtained by using a Kemomimi Potion in a Rabbit, if spawned using the Spawn Egg, it can be tamed with Golden Wheat, you can heal them with any kind of carrots and wheat, you can also give them a Vanilla Chestplate for them to wear with Shift + Right Click, that also opens up their inventory.

Dyes (Light Gray, White, Yellow and Pink) can be used to change their colors.

The Queen Cow can be obtained by using a Kemomimi Potion on a Cow, if spawned using the Spawn Eggs, they can be tamed with Golden Wheat, which you can also heal them with, you are able to give them a Chestplate to wear with Shift + Right Click, that command also opens up their inventory; They can be milked with a bucket or a bowl depending on the variant.

Black, White, Red, Yellow and Brown dyes can be used to change their colors.

The Princess Cat, can be obtained by breeding two Queen Cats together, has pretty much the same stats as a Queen Cat, being a tiny bit faster, they cannot equip armor quite yet but with Shift + Right Click, you can open up their inventory.

Dyes (Black, White, Orange and Gray) can be used to change their colors.

The Princess Dog, can be obtained by breeding two Queen Dogs together, has pretty much the same stats as a Queen Dog, being a tiny bit faster, they cannot equip armor quite yet but with Shift + Right Click, you can open up their inventory.

Dyes (Black, White, Gray and Pink) can be used to change their colors.

The Princess Bunny, can be obtained by breeding two Queen Bunnies together, has pretty much the same stats as a Queen Bunny, being a tiny bit faster, they cannot equip armor quite yet but with Shift + Right Click, you can open up their inventory.

Dyes (Light Gray, White, Yellow and Pink) can be used to change their colors.

The Princess Cow, can be obtained by breeding two Queen Cows together, has pretty much the same stats as a Queen Cow, being a tiny bit faster, they cannot equip armor quite yet but with Shift + Right Click, you can open up their inventory.

Black, White, Red, Yellow and Brown dyes can be used to change their colors.