Rukia looked quite excited. She hadn't trained much since she arrived on the TARDIS. And when she did, she didn't dare use her Shikai, nor did she use her Kido. She practised other things. Used the narrow halls of the TARDIS to practice Shunpo accurately and effectively.
"Not that many people get to see Kido" she explained as they walked. "And not all people can see us when we fight. It takes a certain level of spiritual energy and power to see us. You will see what I mean soon"