Mouichido, Anata to Hatsu Ecchi.

"Did we have sex?" Having sex for the first time in order for her to make a fresh start with her amnesic ex-boyfriend. But her body is corrupted by the sin of lies... Too scared of sex, Maho broke up with the man she loves after repeatedly resisting his advances. While still unable to forget her long-lost love, she gets a call telling her that Naoto, her ex, was in an accident...! Visiting him at the hospital, she discovers that he has slight amnesia and doesn't remember their breakup... This time, Maho wants to answer him when he so naturally gets her on his hospital bed. Being caressed all over as though he were trying to find his lost memories, she drowns in pleasure... even though she knows it is but an illusory love...

from Renta!