It's sorta romantic how out of all of the surprise kisses, the one with Yotsuba is the only one he thought was a dream. It really hurts to see her in tears, though
As much as I personally like Miku, I hope Yotsuba wins, as unlikely as it seems. This sorta feels like she's bidding him farewell, and it's totally bumming me out.
It's okay to be a little selfish, Yotsuba.