its very messed up from what i can see everyone has different experiences and from yuu's pov because he lived in a good family so he couldn't understand airi and thinks its only because of her immaturity. But sadly not every parents deserves a child, having such familes which abuses their child are the worst. We should take others pain for consideration, there are many hidden details which people can have a hard time expressing. You can see from reports of abuse, crime rates not every person are good people. Though hiro-kun was very carzy if only he was actually saved he really looked like a kind person but every person has their bad side, their taint, i dont believe there's purely good people in the world, the ones without taint. Its just that some instances we head to the wrong path. I hope in their next lives they live a happier life
Kedamonotachi no Jikan