During his training as a soldier, Eren was known as someone who never wasted food. This reflects the tough upbringing from his family during hard times and his respect for resources.  

Hajime Isayama, the creator of "Attack on Titan," once mentioned that the character Eren was partly inspired by Light Yagami from "Death Note" and Guts from "Berserk." Both are characters with a strong determination who are willing to do anything to achieve their goals, just like Eren.

Eren has a strong emotional bond with Mikasa, which goes beyond mere friendship or family ties. There are moments in the story where Eren shows jealousy and excessive protection towards Mikasa, indicating his deep feelings for her.

Eren often experiences dreams or flashbacks of past memories, even before he realizes he possesses Titan powers. This indicates that Eren's consciousness is connected to the memories of his predecessors long before he realizes his full potential.  

Although Eren often finds himself in dangerous situations, he has a relatively calm attitude towards death. This is especially evident after realizing his fate as the holder of the Titan power, which only has a limited time to live.

At the beginning of the story, Eren is actually uncomfortable with violence and murder, although he later becomes more brutal as time goes on. This discomfort is evident when he first has to face the reality of killing Titans in human form.