Juxtaposition
/jux·ta·po·si·tion/ n. the fact of two things being seen or placed close together with a contrasting effect.
John Watson, sixteen-year-old new boy at St. Bartholomew's School, is assigned resident genius and nuisance Sherlock Holmes to be his roommate. While contending with schoolwork, exams, sports, friends, foes and family, they are entangled in a web of mysteries that soon seem far from coincidences. Will they be able to work out who is behind them - and, scarier still, will they admit that their friendship has grown into something more before it is too late?
[TL;DR: Boarding school AU. Our protagonists wind up as roommates.]