Summary: The Doctor is thoroughly enjoying showing Ianto Jones around the universe.
It made a change for the Doctor to travel with someone who was genuinely interested in the universe’s varied cultures. Someone who was enthusiastic to learn about the traditions and history of the people they encountered, who wanted to taste the native dishes, explore the museums and galleries, learn the local mannerisms and mores to avoid causing offence…
Ianto Jones was lapping it all up and still wanting to learn more, the Doctor had no regrets about bringing him along. In fact he couldn’t imagine why he’d never invited him before.