I've been meaning to chime in on this one for days so what the hell..
It kind of freaked out our Mara when she realised what was going on, but Dez and Mal finding each other was definitely one of the best things to every happen inside our head

Dez believes there is good in everybody. She is us at our most outgoing, confident and happy - So much so that her emotions used to bowl us over and it actually hurt to have her run the show.
Of all the Parts of ourselves we are aware of, Maledict (Mara calls him Blue) has been through the most and consistently his time running the body has been hard on all of us. Mal is jaded but level headed too. He has no illusions about people and life in general (though he hallucinates plenty

).
Running the body on his own his emotions are absolutely overwhelming too.
They found each other inside and they've been joined at the hip eversince.
It is incredibly soothing to have love for yourselves.
Mara never thought it was possible to feel like that about yourselves.
And as long as Dez & Mal are so close to each other, their emotions mingled,
it actually feels good to feel them in here.
I'm Mr. Meeseeks - Look at me!