What does Genesis 30:15 mean?

Leah said, 'Isn't it enough that you took my husband? Now you want my son's mandrakes too?' Rachel replied, 'Alright, Jacob can sleep with you tonight if you give me the mandrakes.' Genesis 30:15 - Modern Text Bible

(Leah feels Rachel has already taken too much from her, but Rachel bargains: Leah can have a night with Jacob in exchange for the mandrakes.)