2. An ugly girl who comes out with her cute girlfriend(s) and prevents the cute girls from getting any game.
3. "Girls' night out." This is a cockblocker by virtue of its name and implications. There will inevitably be a girl or two in this group who are man-haters. They will brainwash their cute girlfriends into thinking men are bad, players, jerks. They will convince their cute girlfriends that girls need to stick together, no men tonight.
2. Cody: Hey Trevor, that girl is cute. Will you be my wingman and distract her ugly friend while I go talk to her? Trevor: No way dude, her friend is hideous!
In this situation, the ugly girlfriend is cockblocking her cute girlfriend.
3. Jessica: It's girl's night out! Yayyy no guys tonight! Ok girls, remember, we gotta stick together. Don't get sucked into any man-traps!
Person 2: Mmm... probably but I just smashed him yesterday, sorry.
Person 1: Oh my gosh, you knew I liked him! You're such a cockblocker!!