Sherlock starts sending Billy to all his face-to-face meetings with Mycroft and Mycroft’s pretty annoyed about it, but then Billy deduces things about him that not even Sherlock has ever noticed and it completely throws him off. He starts trying to ‘mold’ Billy over time the way he was never able to really lead Sherlock as an older brother, until one day Sherlock notices Billy’s changed mannerisms and he’s viscerally jealous and he’s not sure of what/who.
⬡ Shiggins/Mylock








