I'd also weight in with the health and safety aspects. I'd be expecially careful of allergies as many have quite extreme reactions to insect bites (someone I know had a very serious reaction to a single bite from an ordinary garden ant and was hospitalised for it). Infection is less of an issue so long as you are careful about it and made sure any bites were cleaned. I'd start by cleaning the skin with steriwipes before you started (as a major source of infection is not necessarily the insect mouth but the normal flora on the skin of the person being bitten) and end with cleaning the area fully after the bites have been made. An ideal situation would be to use insects that have been sourced from a clean breeding farm such as the maggots they use for medical purposes which have been specially bred in sterile conditions. However, I don't think you can get ants or any other insects with that pedigree at present. Though there is a potential market for someone to exploit if they can get hold of the equipment to sterilise any insects. If anyone does and is looking for someone with science background to consult, I am willing to do so provided my fees are met...

Personally it is not a fetish of mine, mainly because I have worked with insects in the past a lot and they have no fear or special association for me - just like blood. I think you need the fear/novelty to make it a sexual tension thing - the slight element of danger/edge play. So, someone who has no fear of them at all is unlikely to find any special thrill from doing this sort of play. And someone who has the fear is unlikely to agree to it....