While the vines start covering you, they also start secreting some sort of cold, slick substance onto your body. You can feel your entire naked body shivering at the touch of the slime covering you, a tingle which subsides as it adapts to your body temperature. Within the slime, thin black lines seem to form. You run a hand across it, and it feels a bit hardened...chitinous, like the skin of an insect. You fail to move your hands any more though, because the black layer has spread up to your chest and is locking your arms to your sides. You're surprised your head is still uncovered, but maybe that'll happen later. You are now covered to the neck and unable to move any more, pinned to the ground as the final layer of your prison reveals itself. A lighter-colored shell forms on top of it, now finally creeping up your neck and the last thing you see before the shell completely swarms your face is your entire body, covered in an inhuman slimy shell...
Completely encased, you go into a sort of stasis while your body reshapes inside.