How to design a super power that makes people vomit

[Wordsmith]

No, I'm not kidding.

So I'm interested in running a campaign involving superhumans, using an old Mutants and Masterminds sourcebook as a blueprint. In the sourcebook, there's a character sheet for an NPC who has the ability to make whoever looks at his face ill. I've been trying to figure out how to make this power work in GURPS, but I'm having some trouble. At first I thought Affliction, would work, considering that it allows you to make targets retch just by looking at them, assuming you have Malediction. However, the problem I have with Malediction is that it requires a contest of HT vs Will to work, whereas the NPC I'm trying to recreate has more of a passive ability. That is, he doesn't have to roll at all to make people sick--anyone who sees him has to beat a certain DC to avoid getting sick.

So how can I make this character work in GURPS? Also, its worth noting that this NPC can't turn his power off--he has to wear a mask that covers his face