After the date, two scenes open. LLM and a sex scene. There are no more scenes.
The guide most likely means that these two scenes will begin after getting at least three hearts and using all three attempts or an additional fourth attempt to get five hearts.
In general, three hearts are enough, to get five you need to go through about fifty combinations and pay attention to the needs of the girl, usually there are two, and from this you start choosing options for answers and actions.