PinkieDash. Is it that obvious.

Dashie. The entire episode with Gilda depended on Pinkie's steadfast refusal to allow Gilda to remain alone with Rainbow Dash, and her insuistance to stay at Dash's side. When Rainbow Dash is training at the academy, Pinkie is the one missing her and obsessing about here. Pinkie is unusually possessive of the blue pegasus. (Though several episodes rely on Pinkie's fear that her friends will abandon her. She even seemed desperate when Fluttershy was leaving Ponyville for a solo vacation.)

I always thought that they should be together