AU. John is hired by Sherlock to do house chores and general looking-after right after Afghanistan. It doesn't take long for John to discover that Sherlock would and does sleep with anybody. Clients, men whom he picked up in clubs, etc..

John immediately sees through it and wants to offer Sherlock his love. But Sherlock is ignorant of his issues and adamant that he only does no-string-attached sexes.

Can John make Sherlock realise his thirst?

Bonus if Sherlock has a feeling towards Lestrade, which both John and Sherlock mistake as 'love' and John initially tries to facilitate it because John would do anything for Sherlock!

I'd prefer Sherlock as bottom when in bed though!