|Japanese name:||南 春香|
She is the only person whom Chiaki dares not oppose or be rude to; Chiaki views her as a role model and greatly respects her. This can be seen in her tendency to address Haruka as "nee-sama" instead of the more usual and casual "nee-san"; and the only person Chiaki uses polite Japanese with (even though it is not customary for siblings to use polite Japanese towards each other).
"Haruka" contains the kanji for "spring".
Voiced by: Rina Satō