I've always imagined how amazing it would feel to be taken by tentacles, particular in a CNC setting. Several appendages wrapped around your body, licking, sucking, prodding. The first penetration probably hurts a little but I imagine it feels better as it snakes deeper and deeper. I'd love to feel them become frantic as they approach climax, stuffing multiple tentacles into every hole they find. Then to feel them stiffen as cum rushes through the appendages like water through a hose as it stuffs load after load of cum inside everywhere the cum can fit. Maybe it slowly leaves, cumming and filling as it exits until your entire body is completely stuffed full of warm, sticky cum like a custard doughnut.