Well, we were beating around the bush during all of S1... Yozora and Sena would make a perfect couple, and Kodaka is much better off with Kobato, Yukimura, Rika, or even Maria (if she ever grows up)
At least, this time around we don't get all that bullying nonsense
As for what Sena's hand was doing between her legs, while sniffing Yozora's wig, and ogling at her photographs... obviously it was aiding her relaxation for the forthcoming goodnight sleep