Lloyd can count the number of times that Suzaku has said both he's happy, and that he loves Lloyd on one hand. It doesn't happen before Suzaku turns twenty, (though if anyone were to ask Suzaku, he doesn't turn twenty at all.) Suzaku Kururugi, if you were to ask him, is dead and there is nothing but an idea left. There's a mask, a signal of hope, and a man who wears it all and his name isn't Suzaku Kururugi.
The Empress understands him far better than he ever will, Lloyd thinks. He sees it in the way that Nunnally shifts her head just a little, and Suzaku steps sharply to the right, and kneels, cape fluttering quietly. He sees it in the way that Nunnally helps him remove his mask and cups his cheeks, kissing his forehead when all the cameras and people are gone from the room, leaving a scared teenager and an even more frightened young adult. He sees it in the way that Suzaku fists his hands in her skirts and presses his forehead to her knee, shoulders shaking quietly as she runs her hands over his hair and speaks softly to him, assuring him that this was alright, that Lelouch wanted this.
The Empress may understand him better, but Lloyd knows his devicer better than she does. There are many facets to Suzaku; she owns the boy, the scared, unsure, guilty boy, while he owns the soldier, the leader, the traitor. Lloyd wouldn't have it any other way, because he has no need for the boy; it's Nunnally who needs him, so they can comfort each other.
It's Suzaku's twenty-second birthday when he first says it. There isn't a party; Cecile makes a cake, and Nunnally quickly and quietly has it switched out for one that's exactly the same except edible. It's small, there's no decoration, just chocolate cake and frosting and a few plates. Lloyd thinks all this trouble is ridiculous-- hell, he barely knew it was the devicer's birthday until Cecile had screeched about needing to prepare for it that day-- but it's all rather worth it for the stunned look on Suzaku's face when Nunnally leads him in to the small room where they're already sitting, and helps him take off the mask.
"What's all-?" Suzaku asks quietly, hair messy, face showing all that confusion as he watches Nunnally light a single candle, letting himself be tugged over. "...A-Ah, it's today?"
"What kind of person forgets their own birthday?" Lloyd laughs, though it's cut off when Cecile pinches his thigh and threatens to do more, with a sweet, happy smile on her face. Suzaku says nothing-- Lloyd forgets his own birthday frequently, though none of them can tell if it's intentional or not. Either way, he leans down and blows out the candle at Nunnally's insistence because he can deny Britannia's Empress nothing.
After all that nonsense, Nunnally retires to bed, Cecile to her work and Lloyd drags Suzaku off to run tests here and there. They make it halfway through (which is admirable, really, because anymore seeing Suzaku in the flight suit does bad things to him) before Suzaku's on his lap, grinding against him, kissing him hard enough to bruise. They don't even get their clothes off all the way; the flight suit is pushed down so Suzaku's cock can be freed, and Lloyd's pants are unzipped, coat pushed up so they can grind against each other and the brunet has a moment to grab a clean polishing towel to ensure they don't make a mess.
"Happy birthday," Lloyd says laughingly when it's over, glasses knocked a bit crooked, cheeks flushed, hair mussed, and doesn't resist when Suzaku shuts him up with another kiss, sighing.
Suzaku just rests there for a long moment, relearning how to breathe, and then quietly leans against Lloyd's shoulder, murmuring those words almost before he realizes it. Lloyd doesn't say a word, just squeezes his hips, and lets the world fade out to the sound of their breathing and the hum of the metal and machines all around them.
There are three more times after that, over the span of seven years. Some part of Lloyd is surprised that they've all survived for seven years after everything, and hopes that Suzaku lives to see thirty, just like he hopes he lives to see forty.
They aren't officially together (what can possibly be official about a dead man and a scientist whose only interest is in machines and metal) but there's something there at least, and it's something neither of them question. Lloyd never asks, those times when Suzaku says he's happy, if it's because of him or because of the peace, or because of Nunnally. It doesn't matter. Suzaku's happy, Lloyd has his favorite part, and he's nothing if not a possessive bastard sometimes.
It doesn't matter Suzaku's only voiced it a a few times, it doesn't matter that they don't share tender "I love you"s over moonlit walks on the beach, it doesn't matter that the sex is sometimes awkward and too rough or not rough enough sometimes. None of that matters because Lloyd's studied and figured out his part, and knows what makes him tick, knows what makes him happy, knows when he's happy even when he doesn't say it. And that's enough.
The world is at peace, Suzaku almost dares to smile sometimes, Nunnally rules, Lloyd can continue his research, and Cecile keeps cooking terrible food, and Lelouch finds that he's rather proud of the whole set-up, and completely gives himself all the credit.