This tbh. Though Hyoyeon and Sooyoung give me the straightest vibes out of them all. And even though sometimes Tiffany gets very touchy with Taeyeon and in the past Yuri I think she is way too christian to even consider something like that. Not to mention that she likes to fangirl over boys in every chance she gets meh.
And I'm 1000000 % sure that Yuri is a lesbian. There is just no denying about that. I firmly believe that the actresses rumor was true. All the clues lead to that. And I get many lesbian vibes from Taeyeon as well.