Mizuno Seiya (水野 星夜) is a new transfer student, he replaces Najika as the culinary representative. Seiya looks a lot like Sora, causing Najika and Daichi to mistake him as Sora. He egotistical, using "Ore-sama" (オレさま) instead of simple "Ore" as his "I". (Japanese use different "I"s with different degrees of politeness and formality.) He flirts with Najika in the public, causing girls to envy her (in comparison with Daichi, who's more jealous). Although she's rather annoyed with him, she respects his cooking ability. Like Najika, he hails from Hokkaido and is fond of lavender.
Seiya developes a close relationship with Akane. Eventually, she abadons her crush on Daichi and falls in love with Seiya. In the bonus story of the final volume, Akane and Seiya and Najika and Daichi all start dating.