I had a dream of my partner gently but successfully orgasmically pleasuring me with a fingertip just tickling the opening of my bum.
I awoke questioning the reality of the memory. My partner confirmed it was just a dream but upon further development used a toy to penetrate what once had only been pleasured externally in the dream.
My spine has increased in sensitivity through tantric training. When they slowly caressed here with a kiss placed at the top of the spine, connecting my 1st to 6th chakra, I was was brought to tears by the amount of pleasure and emotion they generated from even small slow movements.