Furyou ni Hamerarete Jusei Suru Kyonyuu Okaasan The Animation

Kyouko has incestuous feelings toward her son. The story slowly progresses into the son realizing his own feelings toward his mom. Later on, a friend of her son's, Shin, blackmails her into doing whatever he wants. Slowly, she starts enjoying herself more and more. Will she break or fall for her son?