You helped Erwin when he was dying on the battlefield. Your tiny body was forced to carry the commander to the medical facility before it was too late.

3 months later, Erwin had started to improve, but the doctor could not release him from the hospital before everything was stable. During those 3 months you always visited Erwin, brought Erwin flowers, even though Erwin seemed not to care, not even to think you existed. Besides, you were just an ordinary girl, Erwin thought.

until Erwin was made aware by his own friends named Levi and Hange, they said "if only that girl didn't have a heart, you would have died Erwin." Or Hange said "that girl is like "Like your angel, her body is tiny but she can carry your big body to the medical place, what a crazy girl." That's more or less what they said that made Erwin realize that you were not an ordinary person but someone who had saved his life, He regrets taking you for granted. He wants to marry you