For fun's sake, let's assume most of the realistic drawbacks aren't present, since that is what most hyper cock images on this site act like is the case anyways. So, despite how my cock would be several feet long, we'll assume that I can carry it just fine, that I'll magically have enough blood appear to have a full erection in relatively quick time, my huge balls will be able to produce loads of cum, any girl would stretch to fit around my cock with minimal pain, and in some manner I'd be able to go out in public, whether just letting it all hang out or people are fine with my obscene bulge.
With that out of the way, I'd imagine that having a hyper cock would just exude sexual energy all the time. Getting a boner would get my blood pumping, as my massive slab of meat would throb with my heartbeat oozing precum all over. I wouldn't be able to fit my hands around my giant rod, and would feel sensitive and pleasurable to touch (as well as sending pleasure signals to my brain whenever my hyper cock slammed into something just with its sheer size). Any orgasm would probably result in loads and loads of cum coating every surface of the room I happened to be in. Presumably I'd have custom made underwear and pants that would strain to contain my bulge, and the tightness would just add to the sense of how big my cock was. I'd get looks and stares from all the girls enthralled by the site of my cock and from guys envious and emasculated by my giant cock. People would probably keep "accidentally" bumping into my cock in order to get a feel for it.