Chekov has a habit of borrowing and wearing Sulus' clothes when he sleeps. But the Lieutenant doesn't mind that much because it means the jumper always smells of the Russian and to him that that can never a bad thing
Sulu can't hide the glow in his heart when he sees Chekov glaring at the female officer who's trying to put her arms around the helmsman's neck. So when the Russian finally decided enough is enough, and walks over, staking his claim on the other man by kissing him full in the mouth, Sulu decides he really should get Chekov jealous more often.
A burning fire consumes his mind and the only thing that stops Hikaru Sulu from beating the living daylights out of the three burly officers who threatened his Russian, is the hand on his shoulder and the blue eyes meeting his, asking him not to.
Whenever they argue, it's hard to break the silences and say sorry, not because they don't want to but because neither of them can find the right words.
Ensign Chekov isn't a flowers sort of person, but he resolves to buy them as often as he can just to see the smile on Sulu's face.
It's only when Pavel Chekov snuggles in close, wrapping his arms around the other man and whispering " I love you" when he thinks only the dark is his witness, that Sulu realises he wouldn't miss this for the world.
Commander Spock has always wondered at the ways humans communicate with each other, but it completely baffles him how Ensign Chekov and Lieutenant Sulu can have entire conversations without saying anything
James T Kirk has experienced many bad moments while he is Captain of the Enterprise, but none can compare to the look on Chekov's face when he has to tell him Sulu won't be coming back.
Bones had never really believed in love, always thought it was for the foolhardy romantics and idiots with time on their hands, but when he sees Sulu watching over Chekov in the med bay and catches the smile on the Russians face, he wonders whether there might be more to it then that.
Sulu knows that Chekov isn't that interested in Botany, but it always touches him that the Russian will always listen, no matter how in-depth he goes into the different varieties of Vortroian vine-sweepers
Chekov hates it when Sulu goes on away missions because although he knows that Sulu will come back, he can't imagine what he'd do if he didn't.
Uhura has always been friends with Chekov, speaking to him in his native tongue and sticking up for him when he needs it. She has noticed recently he smiles more then he did and he's more confident and when she sees his face light up in a grin when he catches sight of Sulu, she thinks she knows why
Chekov knows Bones hates it when Sulu gets ill because invariably he always ends up getting kicked out of the med bay for "disturbing the patient"
Sulu knows Dr McCoy hates it when the helmsman becomes ill because he can always hear Chekov and the Doctor arguing in the corridor when he refuses to let the Russian in. It doesn't seem to matter what the doctor says because Sulu always seems to wake up to Chekov keeping a tired vigil by his bedside.
Sulu doesn't mind the cold nights anymore because Pavel always slips in beside him, snuggling close and entwining their socking-ed feet, and somehow it isn't cold anymore.
Kirk has learnt never to tease Chekov about his accent when Sulu's around because the angry glare he receives makes it not worth it and he really doesn't want to get on the wrong side of a man who can wield a sword.
Sulu always hates it when they argue because he always ends up saying things he regrets, and the look of hurt in Chekovs' eyes and the cold silence that always follows afterwards makes him feel like he's lost a part of himself
As the infection begins to take over Chekov doesn't seem to breathe. He's cold and still, grey like stone and Sulu's panicking now, pleasing with him to wake up and he doesn't care what he has to promise as long as it makes the Russian better.
If you ask Sulu what his favourite colour is he'll always say blue, but he'll never tell you it's because it's the colour of Chekovs eyes.
Montgomery Scott always notices the tone of pride in Chekovs voice whenever Sulu pops up in their conversations, and he's glad the lads found someone because space can be very lonely if you can't share it with anyone
After a particularly violent contact with a yet-unknown alien race, Chekov lies next to a sleeping Sulu, his head resting against the other mans chest listening to the heartbeat that lets him know he's still alive.
They'd never told anybody about their relationship, so Sulu is naturally apprehensive when Uhura comes into Chekov's room to check up on him only to find he's asleep in Sulus' arms. When Uhura smiles and leaves them alone, with no hint of disgust or judgement in her eyes, Sulu finds he doesn't mind who knows, because whatever people say he always wants to be the one holding Chekov when he wakes.
When they first kiss, Chekovs hands are shaking and he's so scared he's going to screw this moment up, but the look of reassurance in Sulu's eyes and the feel of the lieutenants hands steadying his own, tells him he's doing just fine
When Chekov loses Amanda Greyson, he can't stop thinking he's responsible for her death, but when he cries his guilt into Sulu's shoulder, he's glad the other man is there to tell him it wasn't his fault
When Chekov gives Sulu an amber necklace for his birthday to match the colour of his eyes, Sulu can't think of what to say, but when he catches the loving smile on the Ensigns face he realises he doesn't need to say anything.