|Light Novel Debut||Volume|
|Anime Debut||Episode 0|
Runa is rather serious in her studies where she even chose a work place that can give her time to study.She is also a different kind of sadist to Chizuru where she find joy in mocking Ken.Runa had a habit looking expressionless while saying spiteful things to Ken even though most of them became just for fun as she begins to know Ken.
Runa first met Ken in the shop she is working at.It was also the first time Ken went to choose eroge game after listening to Kurimu's suggestion.She is rude and does not hard her disgust at Ken who was picking a game.Later,Runa meets Ken in the school library where she told Ken to give up on the the blue chip seat .
- Due to her working at the game shop,she is very familiar with Ken's taste.