Note: Depending on one's definition of it, this could be considered an "M" rating.
Nathaniel's nipples are sensitive.
Which doesn't say much by the simple statement, as Anders had experience with more than one person's nipples in his lifetime, but he is fairly sure that Nathaniel's are the most sensitive. They certainly are more than his own.
He enjoys the times when he can get Nathaniel to lie back, and to feel how his body reacts when his mouth covers one of the nipples. His reactions are not immediately obvious, but they are ones that Anders feels with all of his senses. It's the way his chest tightens and he draws it back into the mattress. It's the way his breath catches. It's the way that his lips curl into a pleased smile when he thinks Anders isn't looking.
And Anders loves kissing, touching, not just those nipples but the skin around it. This is not a body of a mage locked in a tower and had little exercise, like so many he's had in the past. This is the body of a man who trains every day, whose body might be described in one of the Antivan romances Sigrun reads.
When Nathaniel moans, breaking through his quiet demeanor, Anders knows he is a lucky man.