Shieeeet, this might actually be endgame. Yuuna straight up confessed - and not only that, she’s doing so because she feels her time might be coming.
The events Chisaki’s Dream foretold are coming to pass. But we’ll have to see what’s makes this different. Oddly enough, Yuuna’s confession might be the spark that makes her disappear, since she’s clearing up a regret.
A great villain approaches, though, and the girls that compete for him are all still against the harem ending - keep trying, Oboro, it’ll work. Hopefully.