Which Character Is The Most Immature?

[Sovran Nila]

Out of all of the manga and anime franchises, which character is the most immature?

 

[Warmmedown]

Episode 1 DBZ Gohan? Since he cried for everything and we saw him change a lot and become better able to deal with life, both on the battlefield and off it. He also integrated his fighting, violent parts and the scholarly and non-violent parts.
Episode 1 Bulma too. She changed a lot and became less selfish, respected others more and became a better problem-solver. In DB she'd act pretty demanding and she shot at Goku, plus iirc she planned to take advantage of Goku initially. Episode 1 Gohan in DB had negative maturity since he was unborn.

Hanako in Asobi Asobase is pretty immature (so are the other two main girls, ofc).

I'd also say that Vegeta was immature for an adult for much of Z, but he's not considered immature amongst saiyans. I'd call him immature because he couldn't praise others really, had no life except obsessing over being the strongest and royal saiyan, couldn't stick to the job at hand without getting cocky and ruining it, "SAD FOR YOU!" (dub line), couldn't see other people as anything but a relation or almost like an extension of himself (eg Goku as a rival to him, Trunks as his son for him to make him look good, Nappa and Raditz as his henchmen, Bulma as his drying cloth woman).

Since "maturity" is nebulous and to some degree a social construct (eg in late 20th Century China many people associated "shyness" with being "socially mature", unlike in 21st Century China or in Western societies. Or probably "mature" traits for a man/woman in the 1200s Mongol Empire would be different to in modern America. Being fine with crying at a movie could be seen as mature now for a man in some (sub)cultures, but not in others), I searched for definitions found on google:
"the attainment of one's final level of psychological functioning and the integration of their personality into an organized whole." - wikipedia

 

[SSJ2]

I'd also say that Vegeta was immature for an adult for much of Z, but he's not considered immature amongst saiyans. I'd call him immature because he couldn't praise others really, had no life except obsessing over being the strongest and royal saiyan, couldn't stick to the job at hand without getting cocky and ruining it, "SAD FOR YOU!"

You're calling this guy immature?

 

[Fantastische Hure]

Luffy & Usopp?

also DB-Super Goku