What can be inferred about JB‘s personality from the conversation between Josh and Miss Sweet tea in the poem, phone conversation (I sub for JB)

He is nervous about talking to girls
He does not care about girls
He does not trust his brother
He is overconfident

Based on the conversation between Josh and Miss Sweet tea, it can be inferred that JB is nervous about talking to girls. This can be seen when Josh tells Miss Sweet tea that JB "cowers in a corner a hundred miles away" whenever a girl comes around. This suggests that JB lacks confidence when it comes to interacting with girls and may feel anxious or nervous in their presence.