Since modern romance often ties "love" to physical desire, people tend to forget that in literature (considering this manhwa is an adaptation of a novel with the same title), first love can also be about pure admiration, appreciating someone's beauty, or even a meaningful moment that leaves a deep impression without any sexual desire at all. And that's exactly what we see here. It's still valid to call it first love. You just need to understand that love can take many different forms, and not project or equate your own understanding or views of love onto what Yuri meant when he called it his "first love," because that will obviously make you feel icky. If you still find it creepy because Yuri was 25 while Xinlu was 12, that's exactly why POV matters. We get to see how Yuri himself describes those feelings, and based on what's actually shown in the story, they don't fit the medical criteria or legal definition of pedophilia either.
Its not creepy at all oml u been reading this out of ur ass
Ugh, this story would have been so much nicer (somehow it still is(?)) without that creepy backstory of them. A 25-year-old guy falling in love with a prepubescent or early pubescent child?! I can't look past that, I will try tho.