Preferences: No younger than 13, please. If Harry is a wide-eyed innocent and intensely curious you win.
Scenarios:
1) A true Santa's Lap story, complete with naughty Father Christmas and a Harry who's never sat on his lap before. Points for candy canes. 2) After the Dementor scare in the DADA classroom, Remus keeps Harry after class and feeds him something even better than chocolate. 3) Harry's been wanking and Remus can smell it on his hands. Pre-transformation (like PMS, only sexier!) lust ensues. 4) (RL/HP and SS/HP) Snape discovers Remus's little secret, and decides to have some fun of his own with the werewolf's little pet.