Shiho

Shiho is a girl that Light Yagami used to date at some point.

Plot
After Light kissed Misa Amane, Ryuk mentioned Shiho and Emi as being girls Light has dated before.

Trivia

 * Misa mentions Shiho in her love diary seen in Death Note 13: How to Read in a section where she talks about how she defeated other girls Light dated in the pursuit for Light. Shiho, along with another girl named Emi, are categorized under "other sluts". Misa states that anyone who was never shown automatically loses.