Billy's trying to stay out of the Down mostly, since he told Erik he would. But he has to pop into his apartment sometimes, and also he worries about people getting stuck there so he just flies around now and then to take a look.

Which is how he spots a new face pushing around a boat(?) full of deliveries. Billy had just seen someone go that way and nearly get dragged down, but the longer way around is shallower.

So Billy flies down to settle next to Peter and gives a little wave. "Hey - the water gets deeper this way. If you go around to the left it stays pretty shallow right now. I can show you if you want?" he offers. As he settles the faint blue glow of his powers fade and he smiles at Peter and adds. "I'm Billy."