Grey

Grey, also known by his name Eurus, is a recurring character of the Non-Canon Comics. They are mostly involved with Brown and/or Holmes and Watson.

Biography
Not much is known about Eurus, but it's implied they used to be a crewmate of the Skeld and transferred to MIRA HQ. At some point in time, they were possibly murdered by Red.

Personality
Despite being portrayed as someone who’s grumpy, they’re actually very friendly and down to earth. They often get irritated with Holmes’ shenanigans (similar to Watson) and hate it when people humiliate their height.

Red
Grey is a possible victim of Red. They are mistaken for liking Red.

Yellow (Holmes)
Eurus sees Holmes as a big sibling figure, who is often immature, they also tend to cause conflict with each other, in a joking way.

White (Watson)
Eurus sees Watson as a big sibling figure, whom they like slightly more than Holmes. Eurus often come to Watson for any personal problems.

Brown
Eurus view Brown as a parent figure, they were also the one giving Brown the nickname “Papa Bear” which becomes popular among other crewmates.