Narcissa sleeping around on Lucius with her still being loving to both him and Draco, like whenever Draco says 'My father will here about this' it's actually Narcissa who comes along and deals with it, not that Draco ever realises. Draco wants the latest racing broom, she'll sleep with the store owner to get it. Draco wants to get onto the Slytherin Quidditch team, she'll have a gangbang the Quidditch team at the same time. Draco sees Harry as his rival, she sleeps with Harry to have him treat Draco like a rival instead of just an annoyance.
