Worshiping Raph's body is easy. Raph's mind and heart are strange, complicated, sometimes painful things, but the clean and simple lines of his physical being have always made sense. 
Leo has sparred with this body, held it, watched it bleed, watched it dance, memorized it like his own long before their relationship took on this new dimension. Since then, his knowledge--his love--of it has only grown, and he doesn't mind when Raph wants him to prove it. 
It's simple. He gets down on his knees like a penitent and starts at Raph's feet, taking the time to savor him bit by bit by bit. He lavishes particular attention on what he knows are the most sensitive spots, the places that no one except for him has ever managed to discover. 
He makes sure not to spend too much time on Raph's cock, not wanting to end the show too soon--and he supposes that it's not entirely unpleasant to not be the one left hanging for once. He'll rise up Raph's chest towards his chest, refusing to let his approaching goal tempt him into being hasty. 
And he makes sure to keep talking through it all, whispering words of praise in between the kisses and licks and delicate little nuzzles. Telling Raph how strong he is, how handsome, what a great fighter and lover, what a good owner he is, how good he is. 
Leo makes a point of the goodness as he drags his tongue over old scars, a truth he wants--needs--his little brother with his fiery temper and guilty heart to remember. It's one of the few times Raph will listen to him speak for such a protracted length of time without getting bitchy, and Leo intends to take advantage.  
It always ends with a kiss on the lips, with Raph seizing him and tackling Leo to the bed, offering him reward for his service. It's even easier to let go than usual, because Leo sags into his brother's grip with the sense of a job well done. 
The times when Raph wants to worship him are different. 
Instead of one kneeling and the other standing, Leo is usually placed on the bed, lying down, to be turned over as necessary--unbound for better access, although he knows better than to move. Raph's touches are rougher, his kisses have more teeth, his words of praise far more crude. 
But it is still praise, in the end--still worship. Raph worships him, even when so much of their sex life is supposedly centered around degradation. It feels....odd. Not uncomfortable, not really; Raph would stop if it did, might even notice discomfort before Leo did. Just odd. 
"You ain't used to this," Raph murmurs once, soft in his ear, in the blurry hot moments before worship takes on a new form. "Ain't used to know how great you are." Leo just swallows and just shakes his head. 
Raph grunts. "Well, like I said, I ain't a liar. Remember that." And Leo does, he will, even on the days when all of his demons are begging him to forget. The thought is frightening in its strangeness, but he clings on to it anyway. 
His brother pushes him to the blankets and worships his inside, his gentle strokes filling him in more ways than one. He keeps touching Leo throughout, murmuring him, worshiping him with the relentlessness that only comes from a true believer.