Rui

Guy protagonist in My Dear Cat. Rui is the handsome young man that Mizuki meets. He is heterochromic, meaning his one eye is brown and the other blue. He acts just like a cat, getting Mizuki to think that he might be one. The cat that Mizuki finds is actually Rui's cat. He is also one year younger than her and is applying to the same university that she is going to.