First and foremost, it will always be Kris. I Still believe in them and though their not together at this moment, I hope in the future they can settle their differences, forgive/forget and even just become friends again. I think Taozi needs Kris in his life, just the way he always admired and looked up to his ge makes me sad to think of what they've lost in a short amount of time.
Second of course, would be Sehun. I think Sehun is Taozi's rock, a bright light for him, they've always been good friends but with the absence of Kris, I think Tao has leaned more on Sehun than any other member. I think Sehun brings out the kid in Taozi, all smiles and happiness. I'm just glad he has such a good friend to turn to during these hard times.