Whilst Harry is busy staking out the ministry in preparation for their attempt to retrieve Slytherin's locket, Ron and Hermione are left to their own devices at Grimauld Place. Set between chapters eleven and twelve of Deathly Hallows.
Ron and Hermione's time at Grimmauld place over the summer before 5th year is probably the longest we go without knowing what is happening to them. This is my take on how they spent their summer together. *Fluffy moments, dramatic ones, some jealousy for good measure. 3rd person, Hermione's perspective, Ron/Hermione, hints at Lupin/Tonks. Good to read between GoF & OoTP.*