Anime characters don't always look their age. Sometimes it's a case of early puberty, as is true for Hotaru Ichijō of Non Non Biyori. Other times, puberty shows up later than it should, as is Honey-senpai's problem in Ouran Host Club. Every so often, a character's appearance is utterly inexplicable. In Masamune-kun's Revenge, Kinue Hayase is the 42-year-old mother of two teenagers, but she looks exactly like a little girl.
Excluding characters who are thousands of years old, here are a selection of anime characters whose physical appearances don't match up with their age.
Mitsukuni Haninozuka (AKA Honey-senpai) is actually one of the oldest characters in Ouran Host Club. He's a third year in high school, but he looks like a pre-schooler, and he milks the heck out of his cutesy appearance as a host.
Despite his unassuming looks, he wields great power over the considerably larger underclassman Takashi Morinozuka.
Leorio Paladiknight is 19 years old, but he's often mistaken for a middle-aged man. When Killua mocks him for being old, he responds by insisting that he looks like a teenager. While his claim might be hard to back up, for the 11-year-old Killua, teens probably also seem relatively old.
Kinue Hayase — 'Masamune-kun's Revenge'
Kinue Hayase presents one of the most extreme examples of an anime character who doesn't look their age. She's a 42-year-old mother of two, but you'd probably guess that she was in elementary school. Her cute, flirtatious nature is a source of major embarrassment for her kids.
Looming at a massive 6'7", the sorcerer Stiyl Magnus looks like he's well into his 20s. For this reason, it comes as a surprise to most that he's only 14. His unassuming age helps him out when he wants to illegally purchase cigarettes, since who on Earth would believe a minor could be almost seven feet tall?