As a man, some things were so far out of his league. That he did not even think about them. But just because Derek did not think of them. That did not mean that they did not happen.
One of those things that happened on the regular that Derek had not really put much thought into, was the menstrual cycle. But now Derek was doing nothing but thinking about that.
Emily was on her period. She was menstruating. Emily was on the rag. She was surfing the crimson tide.
Derek had not skipped biology, and he had paid attention. He knew what Emily was currently going through. At least in theory.
It was fine, absolutely fine.