Himitsu.

• A Passing Story
A school doctor recounts a romance from her own school days.

• Pink
A love triangle. It's set in the same school as "A Passing Story."

• Romance
A couple from the same school as "A Passing Story" and "Pink."

• Lover
Continues "A Passing Story" story in the present.

• Secret Love
A girl deals with heartbreak.

• Sigh
Shiratori, now in college, despairs of ever finding love.