[ He's sad the hug doesn't have the intended effect, both because he realizes how much he hates to see her sad and... it's tough, knowing that the right thing to do is to comfort her in some vague way and just let her cry it out, probably lessen their attachment so it hurts less in the end.

Yata has never been very good at that, and his arms tighten around her slightly. ]

... please come with us. [ The words are soft to keep his voice from cracking. ] I know it's really selfish, and everyone in your world needs you, but Kou-chan I-- we need you too...