When the K2 approaches the table, Mal rises and extends a hand, just as with Deimos. he grips the other's forearm and shakes firmly. "I'm Mal, that's Tock." He gestures to the human seated beside him then to the tiefling. "This is Deimos. Pleasure to meet you."
With the revelation that Mythra is in fact male, Mal leans over to Tock and stage whispers, "Hunh, I never would've figured." Mythra's shrieking elicits one more reaction, before Mal returns to those seated with him, "Is he sure?"
After the shrieking subsides, he returns to the banter, "How likely is Tock to return from an adventure with you with all of his hair?" While the question is posed in a jovial tone, Mal is plainly serious. Maybe not about the hair, but about getting burned.