Yuu is sad because Chiaki lied and left him for Tori.
Yuu to Chiaki: "Do I have to spell out that you're the one I like?!"
Chiaki sees Hatori and Yuu talking in the rain (ep5)
Hatori and Yuu allegedly kiss (ep5)
Yuu brings The Kan limited edition to Chiaki (ep5)
Chiaki and Yuu at the New Years Party (ep6)
Chiaki and Yuu at the New Years Party (ep6)
Chiaki and Yuu leaving Hatori at the New Years Party (ep6)
Hatori, Chiaki, and Yuu (ep6)