Is there anything else on this site anywhere close to Eternum in terms of quality right now? The only games I can think of are Being a DIK and Artemis and while they're both solid neither of them are this good.
It's liable to be a long couple of months.
I've seen others mention Ripples, Pale Carnations, I'd also recommend Mist, its not Honey Select, but custom stylized models that are pretty good and has an interesting story. Of course Once in a Lifetime doesn't even need to be mentioned, but might as well. It looks older but still very good quality and story by Caribdis.
Would also recommend Projeckt: Passion, Oppai Oddysey,and Desire of Fate. It's hard to beat everything Eternum has but these games all share similar traits in different aspects.
Something a bit more serious but high quality would be Desert Stalkers, very different from Eternum but good story, characters and worldbuilding.