@bangtangurl91230 Tae doesn't tops most of the time. Being Dominant and being Top is two different thing. :) Since Tae is older, Kook lets him have the upper hand, but if it's a matter of say any decision making, Kook would be more reliable. And, most importantly, even being the younger, he has some power over his hyungie, and that's visible. It makes him the Alpha in their relationship. Well, we are no one to have a say in this. It's their life.
I love it when Tae overpowers Kook and does just anything to him. They are the definition of 'cutest couple' and I'm not even exaggerating! XD