I don't really need to breathe. I just pretend so that my colleagues/friends get less freaked out. After all, they think I'm unnatural already with my "human glow stick" skin (All the cursed fire in my veins tend to make me glow in the dark), if they look at me not breathing, then, well, I've already sent a few people to the asylum already from freak outs.
The reason why is because I can extract the oxygen from the air around me directly into my body. I can use it to give me huge bursts of energy at once. This, I can also do in water as my skin will have the same function as gills (just much more potent)