@Veiled AngelUnder certain circumstances, Mars could feel it best to fuse with her, if for no other reason then to keep her from getting hurt in the crossfire.
Also, fun fact about Marra Mambas, while they are veritable powerhouses, all if them are prone to emotional imbalances due to the amount of power they contain puts stress on their minds. This can be alleviated with a proper companion(Zoeisites) that are able to, in a sense, wipe a Marra's memory of any mental episodes or what caused them. No Zoeisite, no memory wipes, which mean the strain will continue to build until he a) finds an alternative way to relieve it, or b)Snaps, followed by a wild bought of berserker behavior that can only be stopped by poofing them.
This is just a long way of saying that not only is Mars easy to trigger, but doing so pushes him ever closer to his inevitable demise as a sentient being.
Now then, wasn't that a fun fact?