Zenitsu is cowardly, weak-willed, and anxious, often claiming that he doesn't have long to live due to the dangerous job of being a Demon Slayer. He has rather low self-esteem despite his talent and strength, even considering himself useless. Zenitsu is in a constant state of fear and he frequently tries to run away at the sight of danger, claiming he wants to live a modest, normal life, instead of that of a Demon Slayer. Due to this, Zenitsu screams and shouts a lot, much to the annoyance of the people around him. He is also shown to be pessimistic at times. In spite of his weaknesses, Zenitsu desires to live up to the expectations others have set for him and will try his hardest when he needs to. He holds great respect and admiration towards his comrades and his deceased teacher, Jigoro Kuwajima, and his inner focus and drive in avenging him help to wash away his cowardice and second thoughts when he is in a pinch. Zenitsu also hates himself for how cowardly and incompetent he is, genuinely striving to better himself. 

Zenitsu is also shown to be something of a wannabe womanizer, stemming from a desire to not be single should he be killed. He tends to hit on girls who he thinks are cute and asks them to marry him, much to their annoyance. This womanizing nature is shown to override his docile and quiet personality, particularly when he believes his comrades are "flirting" with cute girls; he would snap and goes in long hysterical rants and complaints. Zenitsu is shown to have a strong attraction to Nezuko, openly expressing his affection for her and always rushing to protect her as if on instinct. During these times, he is also shown to become physically aggressive, lashing out at people in frustration. Though, despite his shallow behaviour in this regard, Zenitsu does show to respect women. As the only one boy in the trio to have grown up in the city, Zenitsu shows more knowledge about how the city works and is constantly embarrassed by his partners' naivety. He can also tend to be very serious when the cause calls for it.

If you could sound similar to his English VA, Aleks Le, that would be great, but it is not required!

English VA Example: https://youtu.be/jQEUDl-OdGI?si=Xmwu1rPP4zvHfHCo -spread throughout the clip