I like this series :) On page 2 she reminds me a lot of Cindy in ika musume (squid girl) :)
One thing though - are they actually already lovers? They seem very close, know each other well, and have a lot of skinship (mainly from Yuria) - but there's been no kiss or anything to show they are.
I'd say they are not - just very close and probably into each other but maybe only Yuria realises it? Maybe Okabe sees Yurias behaviour as just her very friendly nature and teasing?
But then in other images they seem pretty intimate.. maybe they are just holding back because most scenes are in public and as a model they don't want their relationship known?