Carolines With Asparagus And Lemon

• 2 dozens asparagus
• 1 lemon (whole)
• 1 salt and pepper
• 1/2 butter sauce
• 65 gr crab meat
• 60 ml water
• 55 gr butter
• 16 ml cream (heavy)
• 8 gr shallot (chopped)
• some salt and pepper