Are Watari and Kaori a couple by the time she is hospitalized after missing the gala violin concert?

Question

One of the reasons Kousei uses to rationalize never making a move on Kaori (and the real reason being his indecisiveness, in my opition) is that she is Watari's girl/romantic interest.

Watari and Kaori are never shown as a couple, or even having anything between them beyond friendship, when they are together onscreen. Kaori doesn't seem to even give Watari the time of the day.

In episode 17, he tells Kousei "For the woman I love, I would drink even muddy water", while trying to usher him into visiting Kaori. His attempt at pushing Kousei into going there seems a perfectly fine wingman behavior, so I am quite confused.

So, there are a couple unknowns here:

In the fist episode, it is clearly stated that Watari has an interest in Kaori (and it is what starts the whole "Friend A" Kousei's self-demeaning thought train). Did they move forward?

Is Watari really wingmanning Kousei when he tells him to go visit her?

Answer 1

At least judging from the Anime Series, they never have been a couple. Here is why I believe that:

1. Just after the group of friends went to visit Kaoris concert for the first time, Watari does notice that Kousei has a thing for Kaori. I mean the dude is a piece of bread but even he noticed.
2. He does hardcore wingman Kousei to go see Kaori once she's in the hospital. Apart from the fact they have nothing in common he still seems too interested in all other girls as well, thats how I'd judge him not really bonding with Kaori in the first place. :)