Imagine your OTP passionately making out on the beach, the moonlight illuminating them so perfectly… until the one on top gets their ankle pinched by a roaming hermit crab.
Imagine your OTP going to the supermarket with their child, they get distracted just a second and the kid is gone. Person B freaks out and runs through every aisle looking for the kid, while Person A stays quiet. Person B comes back to yell at Person A that they are not helping, just to find them with the child in the cart.
Imagine person B of your OTP is a touchy-feely / horny drunk. And while they’re at it, person A casually deflects their attempt at seducing (verbally or physically) like a pro and just babies them until they can be tucked in bed. Bonus if person A lies in bed all morning whispering all the embarrassing things person B said into their ears while person B tries to cover them with a pillow and constantly swats at person A to make them stop.