Severus is the one in the books I most identify with and for me, he's the most fun to write. I'm glad you didn't think he was OOC!
Dumbledore's thong was my way out of writing a sex scene on an airplane while children were there. Also: I see Dumbledore dancing around his cottage in only his thong to "The Thong Song" by whatshisface.
It is an image that brings tears of laughter to my eyes.