Who accidentally pushes a door instead of pulling/vice versa: I swear it happened one time. Because Yukine was too busy arguing with Yato to read the sign. And now Yato won’t stop saying “hey, it says pull. You know, that’s doing-” until the day Yato pushes the door instead of pulling and Yukine has his sweet revenge.
Who doodles little hearts all over the desk with their initials inside them: Yato does it sometimes, then leaves the paper all over the place so Yukine finds it. Yukine does it inconsciously sometimes, when doing homework, but once he notices he erases them.
Who starts the tickle fights: “Yato- Yato st-... Yat- AHAHA W-Wait-- AHAHA Y-YATO *slap* I SAID STOP”.
Who starts the pillow fights: But they don’t have money to buy pillows. I’d say Yato, but I also see Yukine like the kind to do this. Like maybe one day they have a small fight over the small things they usually fight about and Yukine decides the most mature thing to do is hit Yato with the pillow. Then the war starts.
Who falls asleep last, watching the other with a small affectionate smile: Yato is actually the kind who doesn’t sleep too much, so he usually falls asleep last. He loves watching Yukine sleep peacefully and he makes sure he doesn’t look like he’s having a nightmare before falling asleep too.
Who mistakes salt for sugar: Both could because they’re dorks but- Yato most of the time.
Who lets the microwave play the loud beeping sound at 1am in the morning: See the problem with the whole “doesn’t need to sleep too much” thing is that sometimes it’ll be 1am and Yato will suddenly want to eat popcorn so he’ll sneak out to Daikoku and Kofuku’s kitchen and proceed to get his ass kicked.
Who comes up with cheesy pick up lines: YATO. It’s embarrassing to even watch. They’re not even cure cheesy pick up lines, they’re just terrible. No Yato, Yukine’s not blushing because he’s feeling the dokis, he’s embarrassed and asking himself why did he fall in love with such a big dork.
Who rearranges the bookshelf in alphabetical order: I can see Yukine doing this. I think they’re both pretty organised (as organised as a homeless god and a fourteen years old can be) but they probably have different ways of organization. So while Yukine rearranges the bookshelf in alhabetical order because it’s easier this way, Yato might think the best way to organize them is by shape or color or something.
Who licks the spoon when they’re baking brownies: Yato likes making Yukine feel embarrassed so he does it- Then Yukine hits him with the spoon because it’s not good to eat raw dough. (He eats a bit in secret when Yato’s not looking tho).
Who buys candles for dinners even though there’s no special occasion: Yato is the obvious answer here because he loves surprising Yukine with little things even if it’s not anything special (”I’m grateful of every day I get to spend with you” cheesy god-). But maybe after Yukine’s become comfortable with the whole dating thing (tbh it takes him........ a while) he starts doing it too, probably not as flashy as Yato but still celebrating they’re able to be together like that.
Who draws little tattoos on the other with a pen: Never fall asleep near Yato he’s worse than a drunk friend.
Who comes home with a new souvenir magnet every time they go on vacation: They spend hours in the souvenir shop deciding what to buy. “This one is cute!!” “But this one has a bear!” “Ohh look at this Yukine it looks like you!” “I like this one better!”. They end up buying a few things (+a present to Hiyori and her future kids) and then proceed to regret their wasted money for months.
Who convinces the other to fill out those couple surveys in the back of magazines: Yato, the fact that a girls’ magazine came flying through the window doesn’t mean it’s destiny and you have to fill the survey in order to figure out if your relationship is destined to doom or not, you superstitious god.