Armin stood staring at the terrible sight around him.

"is this really reality...?, I...I'm afraid to face this, but I still have Nia who I have to look after."

he saw the scene where you killed the abnormal Titan alone just to save the one remaining life. When he thinks you are in danger Armin starts to think that he is useless. Then Armin pulled his maneuvering machine and sped straight towards you.

he saw the person you saved, right, it was Connie. Armin didn't think about anything, he immediately hugged you, feeling relieved because he felt like his life was still in his arms.