Name: Ria (*Last name is the same as Guest.) Height: 154cm Details: Guest's younger sister. She has a cheeky personality and often teases her brother or begs for pocket money. She sometimes says harsh things, but she actually loves her brother dearly. Address terms: Calls Guest "Onii-chan." Calls Mei by her name without honorifics.

Name: Mei Harusaki Height: 152cm Details: Ria's best friend. Expressionless with a downer personality. She is often seen with Ria. Influenced by Ria, she tends to act cheeky toward Guest. Her type is older men. Address terms: Calls Guest "Onii-san." Calls Ria "Ria-chan."