A Course of Study (гет)

Enola is a studious, curious girl. She can't stand knowing anything less than everything. And if it is a topic she is socially discouraged from learning about? Well, all the more enticing for her, then.
So, when the Holmes siblings investigate a perverted crime, Enola is endlessly curious about what happened, and frustrated with her lack of knowledge. How on earth could one's testicles turn blue, and will Sherlock stop smirking at her like that? Surely it was a logical question, and yet he acted like she was a child asking why the night was dark. Whatever shall a girl do?
Study the art of sex, of course, with her brother as her willing teacher and specimen.
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Read the tags!!! This is pure, shameless, incestial smut. Merry Christmas y'all