I wanted to draw my older brother and I as skelebros! In the scope of Undertale, we would live in the Capital, and he (Calisto) is an architect while I (Ampersand) am an engineer. I'd like to think that in a post-pacifist ending, we help contribute towards the rebuilding of places on the surface for monsters to live.
Ampersand uses fire magic, but his hair isn't indicative of a vital life source or anything. It's purely cosmetic, but is potentially dangerous, so he keeps it "off" when needed.