Singing to Shadowheart by the campfire after a long day of fighting bad guys....
Writing a ballad about Shadowheart's heroic deeds saving Baldur's Gate from the dastardly cult of the absolute...
Embarking on Shadowheart's quest to discover her memories, and then making new ones, together....
Cuddling with Shadowheart and suddenly she whispers to you her real name....
Shadowheart running her fingers through your hair as you sit and watch the stars together, then she says she's happy that she can finally appreciate the moon now that she has escaped from Shar's deceptions...
Using your reaction to jump in front of an arrow that met or exceeded her armor class....
Getting Loviatar's blessing from the priest in the fort and Shadowheart liked watching that so she tells you that you need to do it again every night in order to keep the blessing, and that she happily volunteers to help you....
Using your adventuring money to buy the nicest wine in Baldur's Gate for your date at the lake with Shadowheart....but then reminding her that it's dangerous to drink and swim because you love her and care about her safety more than you value looking cool....
Using detect thoughts to find out what Shadowheart's favorite camp meal is, and then always collecting those camp supplies....no, that's an invasion of privacy, I will never use magic or tadpoles to look at Shadowheart's mind, I'll just ask her normally....
Taking proficiency and then expertise in chef's tools at character creation so you can always make the yummiest meals for your wife Shadowheart....