Based off my nightmare of the “the girl”. She becomes younger when she touches another human being with skin to skin contact she absorbs the memories of the victim in addition to their years of life causing her age to regress. I can't add to the SCP site because my accounts won't link. This is an experimental layout.

Addendum-XXX-A-1”

-Initial portion of Intake interview A with Doctor C. Clark and SCP-XXXX-

Clark: Doctor Chelsea Clark interviewing unknown human female requesting to enter Foundation containment. Unknown female has complied with all demands provided by staff but has been adamant to not be touched.... Apologizes, now how exactly do you know what this place is miss?

SCP-XXXX: Ingrid, though I know you won’t call me that. I know most things MTF agent ██████ knew ma’am. When my uh what would you call it? Anomaly activates I take all the memories the individual had at the time. ███ attacked me, he tried to ███, and failed. Before you ask he’s dead, and no it was not intentional. Though I can’t say I think it was undeserved.

Clark: If you’re being honest I won’t disagree, but how did a young girl like you fight off a highly trained Foundation agent? What’s the nature of your ability?

SCP-XXXX: Thanks but I’d bet I’m much older than you, by quite a few centuries. To answer your question, I cause people I touch to get older while get younger. If someone I’m touching dies I get everything they remember at the time. I can speak most languages, for example. Sadly my long term memory doesn’t seem to fare much better as far as I know.

Clark: Please give me a moment. <Doctor Clark leaves the room for five minutes before resuming the interview. XXXX remains seated and calmly looks around the room.> When did your ability first manifest?

SCP-XXXX: <Appears to think for a moment.> I think I was around seventeen at the time.

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Addendum-XXXX-32-A:

Unlike other living organisms SCP-999 and SCP-343 seem immune to the effects of SCP-XXXX. As observed after an interview with Doctor ███, who in a breach of professional decorum began disusing their new born nephew. This caused SCP-XXXX to become non-responsive to questioning. Saying that more than anything she wanted a family, and asked the doctor to leave. SCP-343 is observed to walk into the containment unit five minites later and hug XXXX, addressing her by name, and saying that she was “Where she’d be most helpful to humanity, and to learn to help the Foundation.” 343 and XXXX proceed to thumb wrestle and converse with each other for a period of twenty minutes.

Investigations into what this means if anything at all are ongoing.

Addendum-XXXX-32-B:

After experiment 24-B-XXXX, where SCP-XXXX was handcuffed and left in a room with two D-class, one male and one female both of whom showed extremely violent inhuman tenancies. Instructions where given to the D-class to do anything they wished to SCP-XXXX and terminate her. D-91029 removes XXXX’s shoes and socks, before picking up a knife. SCP-XXXX enters its Fear state and proceeds to use her bare feet against one D-class, while the other is bitten by XXXX. Both D-class are reduced to dust causing termination. SCP-XXXX turns to the observation window and approaches causing the window to shatter. Doctor █████, who’d personally handcuffed XXXX for the experiment backs into the corner before being the victim of headbutt and terminated by SCP-XXXX. The Fear state ends after an additional ninety two seconds.

Upon the end of the Fear State XXXX falls to her knees looking at her hands, screaming and sobbing saying they’re covered in blood despite being perfectly clean. Unable to calm her medical staff administer a sedative before returning her to her containment cell. Upon waking SCP-XXXX starts to cry for several minutes having curled into fetal position. SCP-999 is observed sliding under the door of the unit before enveloping XXXX. 999’s usual effect of spreading joy functions as normal and no harm comes form exposure to XXXX.

Note: It would appear these are special cases as SCP-XXXX was observed having an effect on other anomalous objects before see experiment number XXXX-19-C for confirmation.