The Cleric
Many would say you have been blessed with the ability to perform miracles; you can heal conditions and injuries in others, absorbing them into your own body as long as you retain skin on skin contact. You have only ever seen this as a curse. From the moment it became known, you have been used for your powers by countless individuals, and viewed as little more than a valuable tool or mythical creature. The transfer of harm causes you agonising, crippling pain. When you heal someone it is as though every nerve ending in the body is being scraped along a branding iron - and once the process begins you cannot consciously break away or stop it. You can be forced apart from your partner, but if that happens the partner retains their affliction.
Long Description: You wish you could say that the process - the whole painful experience - of your healing, is a blur, but it isn't. It is dense with detail. You learned two things. One is that no amount of violence anyone can ever witness done to others prepares you for violence done to yourself. The other is that you can't escape the marriage with your body.
Even the tiniest of cuts brings it all. Minor injuries like scrapes or even anomalies like small growths are absorbed into your flesh without being displayed on your own body, though the pain is just as intense and all-consuming as if you had acid poured onto your skin. There is no respite; even the tiniest healing sessions hurts like the fires of hell. Larger wounds or conditions will in fact be replicated in your body once the transfer is complete; broken limbs, damaged organs etc. After a few hours, this ‘echo’ of the original injury will heal, but until it does you are faced with having to deal with it and the pain that comes with it.
It has to be a curse; you've never been able to get used to the sensation of your screams locked in by a gag, having to back-up and cash themselves out in your skull. They keep your tongue held down so you don’t swallow your own tongue. They say its a kindness.
You discovered pity for your own body. It was endlessly renewable, this well of pity. Every mutilation drew its unique portion of it. Every amputation subtracted, poignantly, took away - literally - some of who you were. The worst? After a few minutes - or hours; some sessions leave you trembling and raw to muscle - you've nothing to show for it. No bruises, even. It's as if the world wipes away your lived experience and you can do it all over again. Certainly, people make you.
Mechanics: For minor wounds of a recent origin (created within the last week on the target to be healed), you just need to be in skin-to-skin contact with them. You cannot willingly break contact once the healing process has begun, but the target can - or someone else can force you apart - which will have the effect of nullifying all progress on the injury and it will be as if it was never healed: wounds reopen, burns return. In some cases you even gain their injury.
For older wounds (especially those that persist through dawn, for vampires) and larger or more aggravated injuries, your blood is required. When supped directly from your veins it has the power to heal more miraculous damage over time, though time it takes indeed: minutes of agonising pain for you, while the target needs to stay latched onto your skin.
You do not have a limit on how much you can heal, only what your sanity can withstand or until your blood runs out. However, if you heal someone through your blood rather than just skin contact, pause gameplay to ask the target off-game what the worst pain is that their character has experienced, in their life, and have them describe the scene or scenario briefly to you. Because while you are healing them and they are drinking your blood, this is the pain that you will be experiencing, in full. Healing through your blood makes you suffer the lived experience of the worst pain the target has ever experienced in life, you also get a flash - almost a vision - of what it must have been.
(For off-game purposes: they do not need to put their actual mouth to your skin; they can use their own hand and press it to your skin and "feed" off the back of their own hand.)
If it's an especially long wound feel free to ramp the drama of your pain response up over a minute until you are sobbing and begging them to get off. You can start the roleplay as a very low, contained sob as you try to rein in your body’s response.
When the healing is concluded, you go limp - you can choose to be conscious and hazy, fully lucid but exhausted, or totally out. Your going limp signals to the target that the healing is successful, so the timing of the action is in your hands.