Who said "I love you" first?
Harry said it to Ginny during the first time they were alone after the battle of Hogwarts. At hearing the words, Ginny tackled him and kissed him full on the mouth (she'd been dreaming of him saying that since the age of ten). She then told him that she loved him too.
Who would have the other's picture in their wallet?
They both do. Harry has a photo of Ginny from their honeymoon in his wallet. Ginny has a photo of Harry playing with their children on her desk at work (she works as a Quidditch reporter for The Quibbler).
Who leaves notes written in fog on the bathroom mirror?
Both of them. They have to make sure they get rid of them before the kids see (most of the messages are a little NSFW).
Who buys the other cheesy gifts?
Harry. Especially if he knows it'll annoy Ginny (she either yells at him, or snogs him- either is fine with him).
Who initiated the first kiss?
Harry, after Gryffindor won the Quidditch cup in his sixth year.
Who kisses the other awake in the morning?
Ginny. Harry does enjoy his lie-ins. He also enjoys the way Ginny wakes him up (don't ask).
Who starts tickle fights?
Ginny. Harry is surprisingly ticklish.
Who asks who if they can join the other in the shower?
Both of them. Although less so after they had kids (they're both too lazy to put silencing jinxes in the bathroom).
Who surprises the other in the middle of the day at work with lunch?
Harry. He often apparates from Hogwarts during the lunch hour (outside the grounds, obviously) to Ginny's workplace. Her favourite is pasta.
Who was nervous and shy on the first date?
Harry. Ginny doesn't really get nervous that much. She thought Harry's bashfulness was adorable, though. Harry found out he rather likes Ginny aggressively flirting with him to make him blush.
Who kills/takes out the spiders?
Both of them. Although Harry just puts them outside (Ginny is merciless with killing them, a side-effect of growing up with Ron).
Who loudly proclaims their love when they're drunk?
Both of them, although Ginny had better alcohol tolerance. Ron had repeatedly told them to shut up (Ginny doesn't listen, but Harry does).
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