The Guide is your friend here:
See Anna Route
After asking progressively for titjob and handjob in the basement and groping some more, the subsequent visit to the basement will trigger the 5 heart event where she asks to have sex and will automatically pick a route based on the amount of corruption/romance points
So keep Groping and Going to the Basement and your time will come.
Adrian kicks in after you have 5 Hearts with Anna.