Traps are guys that look like girls.
Yandere is explained a few posts above. (by ryusensei who googled).
Tsundere are girls that act tough but actually are really sensitive, take Louise from Zero no Tsukaima or Shana from Shakugan no Shana for example.
I actually have no idea what "fap" is.
^Birthday Sig & Ava from Mikessc88 <3 v Birthday Sig from Imotochan <3