[Zero's been nothing but amicable, considering he's surrounded by what he should hate. He's been good to Yuuki and to Ai, a decent person for them to be around. It must have taken a lot to stand in front of him and not reek with bloodlust for those who took his life from him. It's impressive, admirable, even, but he's not ready, or capable of letting go just yet.
Even more so, when he finishes with 'family dinner', because while Haruka knows he and Ai are Yuuki's family, there's no need for Zero to put it that way. He'd have joined anyway, he doesn't care, as long as he's with his daughter, but the unspoken invitation he's had since he arrived is still a pleasant thing to have.
'Family' is the reason he's sought out Zero, though.]
That sounds nice. I'd like to help, if you don't mind.
[He's no chef, but it's the thought that counts anyway.]
Before that, though, I need some answers Yuuki wasn't ready to give.
[It feels almost underhanded, doing it this way. Yuuki has her reasons but he's never liked being left in the dark, especially when it concerns his family.]
Ren isn't Kaname's. [As if that wasn't clear.] He's yours, right?