For me it's a combination

ID:
SCP 682Class:
KETERExperiment log:
here
ID:
SCP 053Class:
EUCLIDExperiment log: none exhists
Item: SCP-053
Tissue Test Record:
N/A, overridden by O5-Command
Termination Test Record:
SCP-682 introduced to SCP-053 containment area. SCP-682 appears to be very confused, and shows no sign of being affected by SCP-053. SCP-053 appears to be afraid of SCP-682, and hides behind a chair in her containment area. SCP-682 lowers itself to the ground, resting its head on the floor. SCP-053 approaches SCP-682, and after several seconds of hesitation, briefly touches SCP-682 before rapidly returning to her hiding place. SCP-682 does not react in any way. SCP-053 approaches SCP-682 and pats its head, causing it to exhale through its forward nostrils. SCP-053 claps and hops in place several times before embracing the head of SCP-682. For the remainder of the testing period, SCP-682 appears to be in a very docile state, with only two low-level escape attempts being made. SCP-053 is observed to bring toys and other items to SCP-682, and makes several drawings on its forward carapace with crayons.
Staff entering at the end of the test phase are immediately attacked by SCP-682, resulting in two deaths and five injuries. SCP-682 contained and moved to separate containment unit. SCP-053 observed crying for several minutes after SCP-682 is removed.
Notes: The reaction of SCP-682 is notable for several reasons. First, it is one of the few incidents where SCP-682 has come in contact with biological tissue and not entered a “rage” state. Second, it has raised questions as to the physical make-up and composition of SCP-053, in regards to the lack of response of SCP-682. Third, it has provided a possible solution to long-term containment. However, approval for the mutual containment of two highly dangerous SCP items in a single containment unit is not likely.
Those who aren't familiar, lemme TL;DR for you-
682 is an alien lizard that
cannot be killed, and seeks to destroy any and all biological matter
053 is a little girl that drives people insane to the point of killing themselves in some recorded instances
682 didn't attack 053.