Euan was indeed a very tragic character. I don't know if you've read this author's other work Flowers of Evil, but she does have a thing of making the protagonist not end up with the most charismatic male lead haha. And I'm pretty sure she does this on purpose! Like she thinks the romance that didn't happen will mark the readers way more than if the couple really did happen. And hatefully she's right, because I keep obsessed with the possibility of Jeremy x Euan to this day. She made the main character meet Euan first, kiss him first and etc, tropes that usually happens for the main couple. All to mislead us to really ship them. This sadistic author knows exactly well what she does haha
I come back every 4 months or so, but I rarely read the end. Why? Well, I loved Euan, he was the best brother anyone could ask for and I, from beginning to end, shipped him and Gabriel. But they never ended up together, Gabriel even showed total apathy towards him when she came to say goodbye to ray. Like, i get you didn't like him romantically, but this mans a gem, so at least give a proper goodbye. Also, he died. Whyyyyy just whyyyy