
Thank you for correcting me. I did more research and found this on Wikipedia and thought it was interesting so:
"In Japan, the Japanese Penal Code sets a minimal age of consent of 13 regardless of gender or sexual orientation.[46] However, the Children Welfare Act chapter 34 forbids any act of "fornication" (淫行) with children (here defined as anyone under 18 years of age)[47] with prefectures and districts specifying further details in (largely similar) "obscenity ordinances" (淫行条例) like adding exemptions for sex in the context of a sincere romantic relationship (typically determined by parental approval).[48]"

If I remember correctly they're 16 and 26.
I personally feel that as long as the ones involved are old enough to consent (in my country it's 16 and I feel that that's fair) and they're in a happy and healthy relationship then the age gap shouldn't matter.
That said, I can understand people's reservations regarding the subject as I would personally prefer someone that I can consider intellectually equal to me and that has a similar mindset to mine and from my experience, many people don't fully develop and discover who they are or what they believe in and stuff like that in their teens. So as a 26 year old, I wouldn't date a 16 year old. But hey, if they're happy, more power to them.
I don't see the problem with dating someone older...I know he is a minor, but as long as the other guy does not do anything that he does not want is legal, right? ╮( ̄▽ ̄)╭ it would be nice if they wait to go all the way until he is legally an adult though