Not using it. [ He shakes his head as he shrugs. ] Mercury's just fine, alright? It sounds weird if you say "Mercury-san". You can call me by my full name too, if you'd prefer that. Mercury Black.

[ Finger guns.

And as they approach the food stall with the milkshake bars and whatnot, he pulls up a chair for Rei. ]

As for the names, it's serious stuff. Parents started naming their kids after colours as a movement for artistic freedom. Blah blah, boring history stuff.