Information you need to know about the story beforehand or not

A story about Levi and his relationship with Eren.

Levi is the alpha
Eren is the omega

And this is a story about them getting together and becoming mates, maybe even have a family.

(The picture of the cover does not belong to me, it was made by someone else with a lot of skills. I just found it and it worked with the story, it was found on google so credit to the creator!)