The philosophy of the Immolators Guilds is simple: What does not kill you makes you stronger. On levels of vampirism, it extends to what does not emotionally kill you makes you stronger - they teach themselves to endure pain, the only weaponary anyone could possibly have against them, to disarm enemies before even the first strike. It’s horribly effective. Despite this numbing to such violent input as pain, many Immolators remain passionate, and there are many of them which will need centuries to reach a point of emotional purity where they are truly a master of their emotions, without them dying off.
Narayan Steele has probably the closest to the emotional mastery - he stays levelheaded and calm almost all the time, regardless what is thrown at him.
Mercurian Steele on the other hand is almost immune to pain, but his passion, paticularily for the clan, often runs away with him.