Haiiro no Otome

Kagami Tsutako has been obsessed with Ii Azami for 20 years. While stalking him one day, she encounters Ii Azami being hit by a car. When she discovers he has lost his memory as a result of the accident, she decides to claim they are lovers in order to fulfil her lifelong desire. As a result, as Tsutako repeatedly lies one after another they begin to increasingly escalate…
(Source: Japanese = MBS || Translation = DramaOtaku)
~~ Adapted from the manga series "Haiiro no Otome" (灰色の乙女) by Nitta Chiharu (新田チハル).