Yandere stories aren't uncommon in this type of media, so I was expecting some messed up stuff, but I think what really bothered me the most was that it was a romance story between a high schooler and an 8 year old girl. Like, I felt like I shouldn't have owned this manga - I returned it as soon as I realized that's what it was about. She kidnaps this little girl and falls in love with her, and I read up on the Wikipedia that they end up getting married. Plus, there's sexual assault and obviously very graphic murder that happens. That's so messed up.
But hey, if ur a fan of children being forced into romantic relationships with people who murder and assault others, you'll love it.