Before she debuted as a talent, there was a clip that was making the rounds (I have no idea how I'd find it again) of Sakana at a booth at some convention with a woman with generous cleave on display who was sitting next to him who was identified as Urara, leading to speculation that Urara was working with him at the time and/or would be debuting as a a talent. If that really was her, then she's not lying.