A.) A female canine in heat that provides sexual stimulus for a male canine in the purpose of sperm collection.
B.) A real bitch that leads you on for hours/days/weeks, finally leaving you with nothing but blue balls.
A.) Wow, that's a lot of sperm, you really liked that teaser bitch, didn't you, Fluffy? Yeah, you did..yeah. Good doggie.
B.) Yo, last night I took her to Taco Bell, bought her 3 enchiladas, and she still won't fucking put out. What a teaser bitch!