Do you mind if I take an alternate version of allergy that I made up myself?
Severe allergy: Double rainbow
If the character notices a rainbow, he becomes distracted for the rest of the day looking for more rainbows. This translates to a -2 penalty on all tests unrelated to rainbows.
If the character ever gains LOS on two rainbows at once, he must succeed at a composure(3) test or break down crying, unable to perform any physical actions until the GM decides otherwise.

I would also have you char take one of the Vocal range enhancers and have him constantly speak in auto tune.