Here's some testing for different options for labeling.
Most popular suggestion:
Tarquin: Crap, the three prisoners at the bottom of the "E" burned out early. Now it looks like I just really like custard.
Least amount of characters, but hard to see:
Tarquin: Crap, the three prisoners at the bottom of the "E" burned out early. Now it looks like I just really like custard.
Unwieldy, but it kinda helps:
Tarquin: Crap, the three prisoners at the bottom of the "E" burned out early. Now it looks like I just really like custard.
Looks good, but so many characters:
Tarquin: Crap, the three prisoners at the bottom of the "E" burned out early. Now it looks like I just really like custard.
3 Bracket attempts to avoid changing the text at all:
[Tarquin] Crap, the three prisoners at the bottom of the "E" burned out early. Now it looks like I just really like custard.
(Tarquin) Crap, the three prisoners at the bottom of the "E" burned out early. Now it looks like I just really like custard.
{Tarquin} Crap, the three prisoners at the bottom of the "E" burned out early. Now it looks like I just really like custard.
And Bolding them to see if that helps their case:
[Tarquin] Crap, the three prisoners at the bottom of the "E" burned out early. Now it looks like I just really like custard.
(Tarquin) Crap, the three prisoners at the bottom of the "E" burned out early. Now it looks like I just really like custard.
{Tarquin} Crap, the three prisoners at the bottom of the "E" burned out early. Now it looks like I just really like custard.
EDIT: Also, look at the bottom of the format rules, I have a clarification on new lines for speech bubbles!