Belligerent Sexual Tension/Fan Works

Asa and Yoko in Futari wa Pretty Cure Blue Moon fit this, although they're both Type B tsundere—they only tsun around each other. Even in the beginning of the series, when Asa is scared stiff of "Ice Queen Nakayama", they start bickering practically Once an Episode. Late in the series, though, they argue less and start to get along more.
Averted in That Damn Mpreg. Jerkass Bruce Jameson (son of She-Hulk and John Jameson) believes his has this kind of relationship with Tsundere Rebecca Altman-Kaplan (daughter of Young Avengers Wiccan and Hulkling). In reality, she wants nothing to do with him and ends up with one of their Badass Normal teammates instead.
In A Different Lesson, Tai Lung and Tigress take this trope and run with it for more than half the fic, which is, incidentally, one hell of a Doorstopper.
In the Tamers Forever Series this pretty much sums up Takato and Rika's relationship
- Actually a subversion in that Takato is a Dogged Nice Guy to Rika... usually
- Takato also initially believes Rika's hatred of Ryo is secretly this, but in reality she genuinely does dislike him. Ryo for his part, just enjoys getting under Rika's skin
Peggy Sue Fanfic The Second Try actually averts (?) the trope. Living on their own had helped Shinji and Asuka grow past this point, but when they return to the past, they try enacting this trope to avoid arousing suspicion. The key word there is "try".