The benefit is that you get to enjoy a life form in a more meaningful way, that is having and developing an extraordinary relationship with the animal.
You will learn from the animal, and the animal will learn from you. You will go beyond what is normally known as bonding with an animal, that is on a very deep level you will receive understanding and joy from this animal.
As a soul, this animal is special or has the potential to advance as well. Animals advance too, they have consciousness, feelings, and desires. You will provide and be a support for this animal.
The animal will also take care of you, show you love and offer another kind of perception about life, that of itself.
Having done a ritual for this, such an animal will come into your life by whatever way. Be it you will adopt one or it will come to you.
A lifeform such as this will stay with you many life times. And it will be bonded into your existence.
Animals are sacred and need to be valued more than anything. It is a blessing to enjoy them, to take care of them. We have countless lessons to learn from them, the most important one is that of purely existing and enjoying it.
We also have a duty to ensure their survival and more than this advancement as species not only collectively but individually as well as we do.