What is the best way I can be unattractive?

I am a male and I say this with all humility; there's a mildly annoying situation with a younger woman at work who conceals a certain affection for me. This'd be fine if she didn't very occasionally play games too. I'd like us just to focus. Transferring isn't an option right now. I tried. So what's the best way to ruin the fantasy for her (or even just preemptively ensure there's never any of that if you prefer)?

Best can mean funniest (a joke answer) or what would yield the maximum disenchantment for the minimum necessary effort or reputational cost.