"She ended up marrying (rather later than Harry & co) a fellow naturalist and grandson of the great Newt Scamander (Rolf)!"
Congratulations! You have found Love Type #2. Luna is reading The Quibbler upside down when you finally find her. Reaching out to you, she asks if you can help her with some Graphical Equations she's struggling with. With this clue you're half-way to finding the next love type.