@kaminomikan Mistake? No. Hina is cute too and closer to him in age. He is underaged while she is an adult. (In Japan, under 20 is a minor) It is criminal. Akari is just too mature and old for him, she even works as a bar hostess, he is still a kid in high school. It feels wrong in so many senses.
In reality, Japanese couples where the women is older than the man are rare and are disliked by society. It is just culturally different.
@miyako19 well the age of consent in Japan is criminally low legality wise, and kids can even get married between 16-18 as long as they have parental consent. So I'm not sure if it's as bad as you say it is. Not to mention, he just needs a single more year and he's a 20 year old, with Akari being 24 or something like that. There's a 3-4 year difference between Akari and Kiriyama, and that's honestly not bad at all. I've seen plenty of married couples where the guy is several years younger, and sure while it may be culturally not as well accepted, I'm sure it's still a possibility regardless as long as there is legitimate love for one another, and I think Japan is honestly getting less and less worried about more minor cultural taboos as time continues to pass.