Barley tea could also be used to show a character's preference or connection to their roots. If a character has a rural background, they might have a special fondness for barley tea. In a fanfic, this could be explored further, like how it reminds them of their home and family away from the chaos of their adventures in the Rurouni Kenshin universe.
In some Rurouni Kenshin fanfics, barley tea might be used as a simple cultural element. It could be something that the characters drink during a peaceful moment at a dojo. For example, Kaoru might serve barley tea to Kenshin and the others after a training session, symbolizing the calm and traditional Japanese setting of the story.
It might also be used in a more symbolic way. Just as the taste of barley tea is distinct and earthy, it could represent the down - to - earth nature of certain characters. For instance, Sanosuke, who is rough around the edges but has a good heart, could be associated with barley tea as it is a simple and unpretentious drink, much like his personality.