Summary: Sometimes teasing isn't funny for the person you've teased, when they are human and need you. The Doctor discovers that sometimes it's cripplingly painful.
Pleasure in Reverse
When he finally ceased to touch her, then quirked his ususal grin at her and sauntered out of the control room, Rose had collasped to her knees, wailing in pain, not in the good kind of hurt as her body, driven beyond what it could tolerate, took the best pleasure a human could experience and reversed it, turning it instead into the worst torture the body could endure. He never did more than tease, they were fully clothed and had never been anything else. He didn't need to touch her much to finish her.
This scream had been of heartbreaking agony, her body convulsed uncontrolably, slamming her head repeatedly against the grating until she finally managed to knock herself out cold. Normally, or so her education had told her, this could only happen during a post partum, there was a reason physicians told women not to have sex of any kind for six weeks after a birthing. This wasn't supposed to be possible without a birthing first...but impossible and Rose Tyler didn't know each other at all...so she slid gratefully into unconciousness as a Doctor generated reversed orgasm finally began to subside. The last thing she saw was his panicked, horrified expression as he ran back into the console room.
Three hours and five medical texts later, tears slid down his pale face when he learned what he'd done with his teasing. "Don't know when to stop and when not to, me. Need to learn when not to stop, need to stop teasing." He brushed his fingers through her hair, "Before I kill you myself. Single hearted, you. Could've killed you." He told the sedated Rose while IVs dripped into her veins, carrying medicines that would restore health to her nerve-endings and her heart. Her fragile, human heart.