This manga is really confusing to me. Through the whole thing I don't understand why they ...

This manga is really confusing to me. Through the whole thing I don't understand why they like Yuka so much, especially Orie. Honestly, I don't think Orie actually loves Yuka, but he confuses it with sex and the fact that she's going to die so he cares more about her ╮(￣▽￣)╭