|“||I've... been protecting it... because you... said that... this thing is more important to you... than your own life...||„|
|~ Zenitsu to Tanjiro|
Zenitsu Agatsuma (我あが妻つま善ぜん逸いつ, Agatsuma Zen'itsu) is one of the four main deuteragonists of the manga series Demon Slayer: Kimetsu no Yaiba, as well as its anime adaption.
Zenitsu is a powerful Demon Slayer and a member of the Demon Slaying Corps. Although he was originally roped into joining the Corps by his mentor Jigoro Kuwajima, Zenitsu later realizes the importance of the Demon Slayer Corps.
He is voiced by Shimono Hiro in the Japanese version of the anime, and by Aleks Le in the English version of the anime.
Zenitsu is a young man with fair skin and downward-sloped, scared-looking eyes that fade from soft brown to gold. He has short, yellow hair of varying lengths, cutting off squarely at the ends where it fades to a darker orange color, that falls in front of his face in uneven bangs. Before he became a Demon Slayer, Zenitsu's hair was originally black, but it turned yellow when he was struck by lightning during his training.
For a period of time following the battle at Natagumo Mountain, his limbs were temporarily shrunk due to Demonic poison, but were able to return to normalcy afterward thanks to the medicine given to him by Shinobu Kocho.
He wears a paler brown version of the standard Demon Slayer uniform, which consists of a dark brown gakuran jacket, a white belt around his waist and hakama pants that extend, as well as his signature white-triangle patterned, yellow and orange gradient haori. As well as this, Zenitsu also sports a pair of tabi socks, tied at the front in 3 white bows, with the same pattern as his haori, and white-laced footwear.
Zenitsu is a coward; always claiming he doesn't have long to live due to the dangerous job of being a Demon Hunter. He also has rather low self-esteem despite his strength, to the point that he thinks he's actually useless, as seen when he couldn't believe he'd slain a Demon that he had, tricking himself into instead believing that it was Shoichi even though the latter was a young child who didn't possess any form of special Demon-slaying ability. Zenitsu is in a constant state of fear and always cries and 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 in which he just thinks he's useless all the time.
However, despite these weaknesses, Zenitsu still wants to live up to the expectations others set up for him and will try his hardest when he is needed 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 always help to wash away his cowardice and second thoughts when he's in a pinch.
Zenitsu is also shown to be something of a wannabe womanizer; he tends to hit on girls who he thinks are cute and ask them to marry him, much to their annoyance. This womanizing nature is shown to override his docile personality, in particular when he believes his comrades are "flirting" with cute girls, he soon snaps and goes in long hysterical rants and complaints. During these times he's also shown to become physically aggressive, lashing out that them in frustration.
Breath of Thunder Style (雷かみなりの呼こ吸きゅう, Kaminari no Kokyū): Taught to Zenitsu by a former Pillar, Jigoro Kuwajima. This technique increases the user's strength and agility to equal a demon's. There are a total of six styles that can be used with the Breath of Thunder, but Zenitsu was so untalented that he was only able to learn the first of the six styles, which is said to be the simplest. Later on, he was able to create a seventh style when confronting his former senior.
- First Style: Thunderclap Flash (壱いちノ型: かた霹へき靂れき一いっ閃せん, Ichi no Kata: Hekireki Issen)- The user dashes forward and slashes at their opponent with incredible speed.
- Zenitsu has honed this ability to the extent of being able to repeat the dash multiple times in quick succession.He usually goes for Six Fold (六ろく連れん, Rokuren), which means six dashes but has been able to use Eight Fold (八はち連れん, Hachiren) to dash eight times within one use of the technique.
- God Speed (神しん速そく, Shinsoku) - Zenitsu can utilise this technique to augment the speed of his Thunder Clap Flash further. He is only able to use this ability twice a day. After the second time, his legs become useless.
- Seventh Style: Flaming Thunder God (漆しちノ型: かた火ほの雷いかづちの神かみ, Shichi no Kata: Honoikazuchi no Kami) - This is the seventh form that Zenitsu created himself. The user creates a dragon-like creature emitting fire and thunder. This form alongside God Speed allows Zenitsu to move extremely fast, allowing him to defeat Upper Moon Six, Kaigaku. Before Kaigaku died, Zenitsu confessed that this form was unique to himself and that he had created it in hopes of fighting alongside him as an equal.
- (To Tanjiro Kamado) "So you were carrying such a cute girl with you... You were carrying such a cute girl with you every single day... and going about your journey with such joy... Give me back the blood I bled for you!!!"
- (To Kaigaku) "Gramps was not senile. If I'm dirt, you're garbage. I can only use the First Style, and you can use all but the First Style. Gramps died a miserable death because he wasn't even lucky enough to have a proper successor."
- (To Kaigaku) "No, Gramps was never like that. This is my own Style. The Style I created myself. I wanted to fight alongside you using this one day."
- Zenitsu's surname means "my wife" (我妻 agatsuma?), while his given name means "goodness" (善逸 zen'itsu?).
- In a twitcasting broadcast segment for Kimetsu no Yaiba, Gotoge said that his name was pronounced as [Zenitsu→] with a more dragged out "suu" syllable instead of a strong emphasis on "zen" [Zen↑itsu]. The pronunciation also goes as "zen-i-tsu" where usually the n and i are separated by an apostrophe, making it Zen'itsu to not be misread as "ze-nitsu".
- Zenitsu was ranked in 2nd place as of the first character popularity poll with 4,299 votes.
- Thanks to his hearing, Zenitsu is very skilled at playing the shamisen and the koto.