The angle may not make this particularly easy, but that doesn't mean Obi-Wan isn't up to the task. He could use the Force to his benefit if he wanted to, but somehow that seems to be almost a cheat, as if he would be admitting to himself and to Klaus that he can't do this on his own.

So he bites down gently on Klaus's soft skin, then shifts his hand until the angle works a little better. His fingers are already wet from Klaus's body and Obi-Wan suppresses his own shiver of pleasure before he slips one finger inside of Klaus. He's warm and so wet and Obi-Wan has to muffle his moan on Klaus's breast as he pulls back and carefully adds a second. At the same time, he twists his hand and uses his thumb to brush over Klaus's clit.