Um...I'm still going with Hitomi being the endgame. It threw me off that Elios is here too.
But I still think Elios's role basically the best friend next door that knew the girl since childhood and never gets her. (In reality he's not even himself anymore). Hitomi is basically the (jerky) rich dude that shows up and steals the girl's first kiss + feelings (minus the jerky richness).