Assistant Professor Sherlock teaches seventh year John in potions Johnlock fluff :)

Once the rings have been exchanged and the vows have been said, Sherlock and John are ready to settle down and get their fill of the domestic bliss that so often comes with marriage. Unfortunately, nothing is ever that simple for them... and they know the honeymoon period can't last forever. They'd promised each other "for better or for worse", but John had no idea just how bad 'worse' could be.