I am a true monoshipper for Levi (and Erwin too but especially Levi); I cannot picture him with anyone but Erwin and anything else feels so strange that it just seems Wrong to me. Levi's just Erwinsexual

Erwin & Levi to me are that couple that meet and then never want to be with anyone else. They get married when they're in their 20's/30's/40's and then 'til death do they part, and even after that the other never remarries

Plus I just can't imagine Levi clicking with anyone else in the same way or trusting anyone else enough to even let them get that close. Levi has a soft little heart; he's extremely protective of it and Erwin was just The Right Guy

And just as importantly I don't think Levi generally has an interest in romantic/sexual pursuits with others - again Erwin was just the right person, and it made Levi think maybe all those silly/dull things that people were so preoccupied with might not be such a bad idea