The grave or her ex Serge Gainsbourg? Know the existence of such erotic song "Je t'aime... moi non plus" ("I love you... me neither"). But the first song I know about Jane Berkin is from the Japanese drama series 'The Beauty' where they use 'L'aquoiboniste' as their ending theme song. Despite I don't know French, the feeling of the song seems to match the drama.