Per 
Object class: Safe
Special containment procedures:
SCP-4XXX is to be stored in a standard inanimate object storage locker monitored by security cameras. SCP-4XXX-B are to be stored in separate lockers, available to Foundation medical staff. Was medicals staff to run out of SCP-4XXX-B, requests for additional instances are to be forwarded to the level 3 Personnel in charge of the section.
Once depleted, SCP-4XXX-B are to be disposed off in a manner similar to non-anomalous paper.
Access to SCP-4XXX for personal use is to be granted with the approval of no less than two (2) level 2 Personnel, and a detailed log of usage of the object is to be maintained, updated daily and submitted to the level 3 Personnel in charge of the section. Due to the objects anomalous effects, no one person shall be allowed access to more than two (2) instances of SCP-4XXX-A within a period of thirty (30) days, or eight (8) instances within a full year due to risk of addiction. Any personnel found to be hoarding SCP-4XXX-A are to be detained, psychologically examined and given leave on discretion of medical staff.
As of 27/2/2XXX, two (2) instances of SCP-4XXX are under Foundation custody. It is unknown wether these are the only ones in existence. Special efforts are not to be made in order to find more possible SCP-4XXXs.
Description:
SCP-4XXX is a small, white cardboard box (3cm by 8cm by 10cm) similar in appearance to any band-aid box commonly found in medical kits. The exterior of the box is painted white, with text reading “Happy Hearts®” and “always contains 86 Happy Hearts®” written in bright red.
It lacks external markings identifying a manufacturer or set number, and is otherwise indistinguishable from any non-anomalous band-aid box.
SCP-4XXX contains sixteen (16) sheets of sticker paper, each one lined with three (3) pairs of white heart-shaped stickers drawn in a cartoony style. These stickers are hereby referred to as SCP-4XXX-A.
The box itself presents minor anomalous properties. Once one or more sheets of SCP-4XXX-A are removed from SCP-4XXX, it will start “refilling” itself. Once an empty space is present inside the box, a new sheet begins to be “drawn” into the inside wall via anomalous means. Upon being completely drawn it peels itself and becomes an individual with the same properties that other sheets. The rate at which new sheets are produced is of one (1) sheet every six (6) minutes
Once an instance of SCP-4XXX-A is removed from its sheet it behaves in a manner similar to any other sticker up until the point when at least 90% of its glued surface is in contact with human skin living, non-anomalous human skin (testing has shown no effect in corpses, SCP-049-2, SCP-2200-4 or surfaces coated with SCP-1199. Further testing is pending approval.).
Upon meeting this criteria, SCP-4XXX-A will completely adhere to the subjects skin and become intangible, resembling a tattoo upon close inspection. At this stage SCP-4XXX-A will be considered active, and will be unremovable from the subject’s skin until it has been fully filled. Testing has shown that, while it is possible to apply multiple instances of SCP-4XXX-A into a single subject, instances that are stacked on top of each other or over an active instance will not activate and remain as a removable sticker.
Upon being activated, SCP-4XXX-A will start releasing an unknown substance into the bloodstream in small quantities, which acts in a manner similar to Adrenaline Fentanyl, rising the subject’s pain threshold. This facilitates the manifestation of the other anomalous effects present in SCP-4XXX-A.
Whenever a subject carrying an active instance of SCP-4XXX-A receives a cut or other injury that would prompt bleeding (such as acute trauma), the wound inflicted on the subject will not cause blood loss. Instead, the blood that would be shed by the wound will, via anomalous means, be “absorbed” by SCP-4XXX-A, which at the same time will start releasing Urotensin-II into the bloodstream, prompting vasoconstriction and alleviating the symptoms of acute blood loss. It is also believed that a mild euphoric may be released at the same time as the Urotensin-II. Research is still ongoing.
When blood is absorbed by SCP-4XXX-A, the instance begins to gradually shift in color from white to bright red, the hue of which is determined by the amount of blood absorbed.
In addition, it has been noted that the wounds of subjects carrying SCP-4XXX-A or B tend to close twice as fast as those of normal subjects.
Once enough blood has been absorbed by an individual instance (testing has determined that the amount
necessary for an instance to be considered “full” is around 10% of a subject’s blood, at which point the coloration of the instance will be F20C00), it will resurface in the subject’s skin and become removable once again, retaining the coloration acquired. At this time the SCP-4XXX-A instance will no longer be considered active, and will be designated SCP-4XXX-B. Once this inactive SCP-4XXX-B is removed from the subject, it will require a “cool-down” period of around five (5) hours, during which the instance will be unable to be activated.
SCP-4XXX-B has the exact same activation criteria that SCP-4XXX-A, requiring regular living skin to properly function and becoming unremovable when the criteria are met.
Once activated, SCP-4XXX-B instances will behave in a manner inverse to SCP-4XXX-A, releasing new blood into the subject’s bloodstream whenever the subject is injured, although SCP-4XXX-B also releases vasoconstrictors and Fentanyl. This time, however, the subject will still bleed from the injury. The rate at which blood is released is proportional to the rate at which blood is lost, instantly replacing it.
Due to the intangible nature of an active instance, it is impossible to determine wether SCP-4XXX-B transform the absorbed blood into O blood or create new blood altogether. Nevertheless, blood compatibility issues have never been documented, even when the subjects donating and receiving blood via the SCP have incompatible blood types.
While SCP-4XXX-A becomes red upon being full, SCP-4XXX-B becomes black as it gets empty. Upon being fully depleting (having replaced 10% of a subject’s blood, regardless of initial absorbed amounts), the instance will be considered “burned”, at which point it becomes regular, non-anomalous paper.
Testing has shown that a subject carrying both SCP-4XXX-A and SCP-4XXX-B at the same time will not bleed at all upon being injured, as any potential blood loss is absorbed by the SCP-4XXX-A instance and replaced by the SCP-4XXX-B instance, creating new SCP-4XXX-B units as they are depleted. This is not, however, a perfect cycle, as the cool-down prevents straight-away reapplication of new instances.
