Shuusuke would never make the first move when they fooled around.
Just Yuuta's luck, that his brother would take the lead every other area of his life but this one, the one aspect of their relationship where the prospect of total control kind of freaked Yuuta out. No doubt Shuusuke thought he was being noble by allowing Yuuta to control things. Personally, Yuuta was convinced he did it for the ego boost of forcing Yuuta to show him just what he wanted, so that there was no doubt that Yuuta did want him or that Shuusuke had his little brother in the palm of his hand. That's how Shuusuke generally operated: make the rules of the game, then conscript other people to actually play it.
Yuuta wouldn't have minded letting Shuusuke put in a little effort himself, for once. He could stand to get some proof that his own overtures were appreciated, that Shuusuke was just as interested in this thing between them as he was. But that wasn't quite fair, he had to acknowledge; Shuusuke may not have ever been the one to kiss him or touch him first, but Yuuta had never had any cause to believe his brother didn't love him.
So it was Yuuta's responsibility, every time, to figure out what he wanted. It was kind of intimidating. At least Shuusuke was generous with him; whatever Yuuta did, no matter how clumsy, he would react and reciprocate in kind, covering him with kisses and caresses that drove all traces of self-consciousness from Yuuta's body. Once they were touching, things generally went all right. (And he couldn't help but think, in a flush of heated memory, of the sharp press of Shuusuke's fingers against the back of his head whenever he sucked him off, the feel of Shuusuke sucking bruises onto his collarbone, the heat of his thighs grinding against Yuuta's own, the hushed, desperate sound of his breathing as he tried to stay silent, because in this as in all things Shuusuke was a control freak.)
It was the getting there that was difficult. On some days Yuuta's head was filled with ringing doubts, thoughts that froze him up before he could even look Shuusuke in the eye. Stupid, unshakable things, like "What if you look stupid?", or "What if this is another one of his games?" Worst of all was the improbable worry that someone would see him, that his friends or his teammates or his sister or his mom would catch him thinking about his brother like this, doing things to him he could never, ever justify to anyone.
On days like that it was the most Yuuta could do to look at Shuusuke, to lay a hand lightly on his body and try not to hate himself. It was enough. Shuusuke would lean into him, encourage his hands to wander his skin, work his own hands and mouth in slow, thorough deliberation over Yuuta's body, until his doubts had shattered under the waves of sensation.
Other times it all came hot and easy, when Yuuta was heady with desire and he couldn't keep his hands off Shuusuke, who made soft, sharp noises against Yuuta's skin and thrust urgently against his hips and held him so impossibly tight that it drove the breath out of Yuuta.
Sometimes Shuusuke would gasp his name.
(And he shouldn't have found that as hot as he did, especially considering how it reminded him of other memories, childhood memories of Shuusuke calling and laughing his name, that ought to be pure and innocent and not commingled with the feeling of his brother's body clenched around his dick. But at least he wasn't as bad as Shuusuke, who was unapologetic about how much it turned him on when Yuuta called him 'bro.')
Part of Yuuta still had yet to completely come to terms with that part of things, the whole 'related' part. The fact that he wanted to sleep with, was maybe even in love with, the same brother he'd spent seventeen years living with and most of his adolescence hating with a passion, the same Fuji Shuusuke that his teammates still gossiped about and compared him against, the Fuji who continued to be better than Yuuta at everything that mattered -- it was a bitter pill to swallow.
It just figured, a voice in his head would sometimes sneer, that after so long trying to strike out on his own path, Yuuta would find himself back where he started, hanging off the sleeve of his big brother.
But over the last year or two Yuuta had become better at shutting that voice up, as he realized that hating himself was not going to change the way he still needed Shuusuke or kept coming back to him.
And that knowledge was sweetened by the truth Yuuta had inadvertently discovered along the way: that somehow, improbably, Shuusuke needed him.
His adolescent self would have been surprised and pleased, to learn that there was at least one way in which he held the advantage over his brother. That he possessed the key to a piece of Shuusuke's happiness, and that it was his own choice whether to offer it or throw it away.
When he was thirteen he probably would have tossed it. Now that Yuuta was older, he knew how to be generous; and he'd learned to enjoy gifting Shuusuke with his touches, and his kisses, and his not-so-skillful handjobs, and what was probably his love.
It wasn't such a bad deal, in the long run; Shuusuke always ended up giving it back to him a hundredfold.