Humor was not part of his psychoindoctrination. You can't kill Orks or Tau with humor. Therefore, the whole concept is, well, ridiculous.

"I am waiting to see which daemon of Chaos manifests from this sorcerous drink you have imbibed." Foolishly imbibed, he might add. Just look at this place, bursting with heresy. If she suddenly breaks out into some blistering pox, then Nurgle is afoot. If she starts thirsting for blood, Khorne, and if she starts acting, well, indecently, that would be Slaanesh's work.

And he'd do more than sling snack foods at her if such would occur. They might have taken his chainsword, but he still has fists.