Raditz's tail is twitching and wrapping tighter around Bura, I guess he's a little caught up in the moment

A slight bonding moment,since Raditz's weakness is through his tail, Bura is able to pick up on his thoughts once she touches it, since his mental guard is down at the moment. It's also a sign that she's grown more comfortable around him, and even if he's not aware of it, he has too.