| Quote #4
Like a faithful watchdog, she kept an eye on every doctor and nurse who walked in or out of the door. (9.54)
Holger Palmgren is one of Salander's friends. Palmgren is the guy who taught her to analyze "consequences" (11.168) before she acts.
| Quote #5
[Martin's] lady friend joined them for dinner. Eva was a warm, sociable, and entertaining woman. Blomkvist found her extraordinarily attractive. (10.6)
This contributes to the general consensus that Martin is a nice guy. So when we learn that he's a serial kidnapper/rapist/killer, it gives us chills and makes us want to know more about Eva.
| Quote #6
[Bjurman:] "If you're nice to me, I'll be nice to you. […] If you make trouble, I can put you away in an institution for the rest of your life. Would you like that? (11.172)
Bjurman doesn't know the meaning of the word "nice" and has no intention of being a friend to Salander like her old guardian Holger Palmgren. Too bad for Bjurman!