Can you spot the red ribbon of their school uniforms? Japanese middle schoolers are 12, 13 or 14 years old on April 1st, when the new school year begins. So nope, no 9 year olds in these lyrics. And Yuuki's voice provider is an adult by now, in the year 2024 - safe! :)
When I first heard this song in a animation meme 6 years ago I was like “wow this song is totally normal 😊” And now when I saw the eng lyrics now I’m like “UH OH THIS SONG IS A SONG PROBABLY MADE BY A LOLICON”
The lyrics writer LamazeP happens to be head over heels in love with Miku Hatsune who is 16 years old. The age of consent is 16 in Japan. So not a lolicon, nope. (Furthermore, the age of consent in Japan was 13 in the years 1907-2023, including 2017 when he wrote these lyrics).