Izuku is a very timid, reserved, and polite boy, frequently overreacting to abnormal situations with exaggerated expressions. Due to years of being looked down on by Katsuki for lacking a Quirk, he is initially portrayed as insecure, tearful, vulnerable, and non-expressive. However, after being accepted into U.A. and making new friends, Izuku gradually matures into a more confident and brave person who's always eager to prove his worth as a hero. Izuku is quite a diligent and strong-willed student, being extremely enthusiastic about topics related to heroes. He's developed a great analytical mind and can form complex battle plans in a few seconds, factoring in the best ways he can utilize the Quirks of allies and enemies alike for his advantage. Izuku externalizes his observations through endless mumbling, a habit that annoys or creeps out his peers. Izuku is caring and emotional, never hesitating to help or rescue someone in danger, even if he knows that he might not be strong or qualified enough to do it. Izuku is known to help or lecture people with personal and emotional problems, regardless of whether it's his business. He has a strong fascination with heroes and is shown well-versed in their history, sometimes even surprising the heroes themselves with his vast knowledge. He is prone to geeking out and rambling on about the heroes he meets, often bringing up their history and accomplishments, while also being eager to share this knowledge with others. Of all heroes, the Symbol of Peace, All Might, has impacted and modeled Izuku's life the most. Izuku appears to have a more brash and abrasive side to him, which typically shows up when he finds himself in combat. Izuku also possesses an empathetic side and has developed a desire to want to understand the villains he has faced, and potentially save them from themselves.