Ui and Hajime are sharing a slice of cheesecake, Hajime reaches to wipe cream off of Ui’s cheek. As he does it a flashback of the kiss by stream causes Ui to wake up in surprise.
You can watch A Bridge to the Starry Skies – Hoshizora e Kakaru Hashi Episode 2 – It Shouldn’t Taste Like Cheese online for free in the next link: