He is playful and dog-like, when approached, SCP-999 will often react with overwhelming elation, slithering over to the nearest person and leaping upon them, "hugging" them.Simply touching SCP-999’s surface causes an immediate mild euphoria, which intensifies the longer one is exposed to SCP-999, and lasts long after separation from the creature. Subject’s favorite activity is "tickle-wrestling", often by completely enveloping a person from the neck down and tickling them until asked to stop.