No one spoke up if they remembered Usaro's name and where it was mentioned, but at this point it should be alright for me to say that you can find this info out in Chapter 4. I'll just give them the benefit of the doubt and assume they didn't speak up as to avoid spoiling the answer for other people. Also give yourself a cookie if you were able to guess what Usaro's power is.
Batuu: Geez, Usaro talks to much. Wait, is he trying to scare him off? owo